Today in Poorly-Aimed PR Pitching

When you think of PATSP -- and I know you do, all the time -- what sorts of topics do you think of? If you're like my new friends at outdoor marketing company Bernard & Associates, you think of game hunting. Yes, the blog header says that the blog is primarily about indoor plants and retail horticulture,¹ but "cultivating indoor plants" is so close to "killing outdoor animals" that B&A sent me an e-mail anyway.

Doe. (A deer.²)
Aside from the added footnotes and the removal of the client's name, this is the e-mail I received:

Kindest Editor:³

 
This is Jeff Thruston from the Nevada based outdoor marketing company Bernard & Associates and we love your outdoor site!⁴ We have been in the outdoor industry for some thirty years. You may have seen our work with clients like Bass Pro Shops and Sporting Classics Magazine.⁵

We want to reach out to you with a gift from the [redacted], made possible by our friends at [redacted] Club -for you or your website's readers. In addition, we have some important news that affects all of us within the hunting and fishing industry.⁶


We have identified your site as one we wish to partner with.⁷ We would like to invite you to participate in [redacted] Club's Blogger Appreciation Program and receive a complimentary Associate Membership to the [redacted] Club.

⁸

With this complimentary membership, you will receive Fair Chase Magazine⁹ on a quarterly basis along with other member benefits. Please reply with your address so we can mail you your magazine. (*See below for more info on Fair Chase & Associate Membership benefits)

The [redacted] Club is always looking for like-minded Sportsmen and Sportswomen¹⁰ interested in preserving our hunting heritage. We want to get your opinion on upcoming news that will affect us along with some other things we have planned in the near future.¹¹

Benefits of our partnership will include all of the following, beginning now and running through the upcoming months:

· Complimentary [redacted] Club Associate Membership (you are more than welcome to do a contest or giveaway on your site if you are already a member etc.)

· In depth looks at the key issues that affect us as Sportsmen interested in hunting/fishing/conservation and beyond.¹²
· Insider news and photos of big game trophies taken recently across North America as well as trophies entered and accepted into the [redacted] Records.

· Video, photo and editorial content for you to choose from for your site.

 

Please let us know which of the following you prefer:.¹³

1. Keep the membership for yourself (Please forward your mailing address)
2. Host a contest or giveaway on your site for the membership (then send us the winner’s address once you have selected him or her).¹⁴

In addition to selecting your gift (or giveaway for your site) we would love it if you would post this video to your site along with some info on the threat by outside lobbyists¹⁵ in an ATTEMPT TO BAN ALL LEAD IN HUNTING AND FISHING. (See attached .doc on the threats of this lead ban¹⁶)
 

Video direct link
[redacted]

Video embed code

[redacted; also the video was incredibly stupid -- almost no content, but lots of be-very-very-afraid-of-the-evil-environmentalists language]


 

If you have any other questions or comments please let me know. And if there's ever anything in mind in terms of a custom collaboration with your site please let me know and I will see what we can work out.

Looking forward to working with you,¹⁷



Jeff Thruston

Bernard & Associates



--
Find attached images for you to use along with the video above.
Also, we have an important article on the lead ban attached
--
About the [redacted] Club:

[redacted paragraph about the club's founding, history, accomplishments, blah blah blah]

About Fair Chase Magazine and your Associate Membership:

[redacted paragraph about Fair Chase Magazine which pretty much duplicates what was said in the main body of the e-mail about the benefits of subscribing]



 
--
[redacted and redundant bit of names, e-mail addresses, and websites]

The saddest part of this whole thing, I think, is that someone got paid to write it. Someone thought that this would be relevant to PATSP, and e-mailed it to me, and then they got a paycheck for doing so even though there was basically no way it was going to benefit their client whatsoever.

There are PR firms that bother to read the blogs they're soliciting, and learn names, and that sort of thing, and show some basic respect for the other people they're involving. It's not impossible to do, and it would get better results. (There are also PR firms that don't take rejection well. That's a less effective way to go. You should read the link, though, because The Bloggess is way funnier than I am.)

Stay tuned for the lead discussion. It'll be very.

-

Photo credits: Doe by Coolstock, at Wikipedia. Buck/hunter by Matthew.j.obrien at Wikipedia.

¹ I should actually probably re-write that sometime.
² (A female deer.)
³ Strike one. If you can't be bothered to type in my [fake, granted] name in your pitch, then you know how seriously I take you? I've basically already decided no, I don't want whatever you're selling, I don't want to promote your product, I don't care about you at all. Because that's the message you're sending me. It's one freaking line of text. Make the effort.
On the other hand, I am apparently also kinder than all the other editors of the world (the rest of y'all are apparently terrible assholes), and it's nice of Bernard & Assoc. to notice.
⁴ Strike Two. And it's only the first paragraph.
⁵ "Sporting Classics Magazine?" What differentiates "classic" sporting from regular sporting? I'm genuinely curious about this. And is hunting a sport? I mean, I don't have a huge problem with hunting, honestly -- no desire to participate, but whatever rotates your turtle -- and I recognize that there are both physical and competitive elements to it, but "sport?"
I suppose if NASCAR's a sport (and I'm told, repeatedly, that it is, just disguised as driving at high speed in large circles for way longer than any normal person would want to drive at high speed in large circles), anything can be. Maybe I should declare indoor gardening a sport. Lord knows it's way more physical than I'd like, and I suppose it's competitive in some circles: I've seen the posts about the African violet shows.
Mr. Subjunctive, Sportsman. It sounds nice.
⁶ Indeed they do. But just 'cause it's important doesn't mean they're not going to make you wait to hear it, and then only if you download and unzip a .zip file, which contains 40 files, about half of which appear to be references to, or misnamed duplicates of, the other half. It's a curious method for spreading important information.
⁷ For "partner with," read "exploit."
⁸ Not sure what purpose the extra spacing serves here, but it does lend the e-mail a bit of suspense and/or excitement. How many lines will separate the next paragraph?
⁹ I find this name amusing/perplexing. Surely it's only a fair chase if the animals are armed, too. I mean, you could call shooting high-speed, pointy projectiles at defenseless animals from a distance "fair" if you wanted to, but only if you'd consider some guy in camo shooting at a naked, unprotected you "fair" too.

Notice that only the person gets a gun. Fair chase my ass.
Again: I'm not necessarily opposed to hunting, I swear. Particularly when it comes to deer and rabbits. But I do have to call bullshit on the word "fair."
And "Fair Chase" actually just makes it sillier. A fair chase would be something like, the people track the animals for an hour, and then someone blows a whistle and the animals get to track the people for an hour, back and forth until somebody gets killed.
I will concede that hunting is more fair than some of the other methods people have devised for killing animals, because with hunting there's at least the chance that you'll lose track of the animals and they'll get away. Cows at the slaughterhouse aren't as lucky. On the other hand, hunting carries a greater risk of wounding an animal and then losing track of it, so that it dies slowly and in pain, or is permanently crippled, or whatever, which doesn't happen with the cows.
¹⁰ Capitalized for no reason because Sportsmen and Sportswomen are Important! (B & A do get points for explicitly including women, though I'll have to take these points back a few paragraphs later, when they mention Sportsmen without Sportswomen.)
¹¹ Nope, still not telling you about the important news which will affect you.
¹² And by "and beyond," I assume they mean hunting/fishing/conservation IN SPACE.
Don't know what else it could mean.
¹³ This may be my first sighting of the punctuation combo ":."
Actually, period usage is all over the place in this e-mail; one gets the impression that Bernard & Associates doesn't intend to put a lot of work into their blog outreach.
¹⁴ I apologize to any PATSP readers who might have been interested in this, and/or to my brother-in-law, who might be interested if he doesn't already have all those things; I assume they're not going to let me do it now that I've made fun of their pitch. (It's my position that they should write less mockable pitches, and pay attention to which blogs they're pitching. And also proofread: it's not just for sissies anymore.)
¹⁵ As opposed to "inside lobbyists," who are apparently A-OK. But hey, at least we've finally heard something about this VERY IMPORTANT INFORMATION.
Also it's disingenuous to pretend like they don't have their own outside lobbyists working on this too. (Along with lobbyists for the lead mining companies, I'm going to assume.)
¹⁶ Because I do not want to reproduce this entire document on the blog, I'm going to summarize it, in my own inimitable fashion, as another post, later this week.
¹⁷ (as long as I don't have to read your blog, learn your name, or in any other way treat you with ordinary courtesy,)

Question for the Hive Mind: a Reader's Dieffenbachia

A reader e-mailed me to ask about a Dieffenbachia problem, which turned out to be something I hadn't seen before. Neither Google nor my books helped, and the few theories I came up with are mostly not borne out by the facts of the case, so I'm hoping someone out there has experience with this and can at least provide an ID, if not tell the person how to fix whatever it is.


The most alarming symptom is the weird bumpiness around the leaf midribs, often with a brown or tan slightly corky/woody top. This is reported on almost all the leaves, particularly the oldest ones, and are getting larger over time. It looks like the bumps mostly appear on the top of the leaf, but in at least one case, the reader provided a photo showing the woody/corky thing happening on the underside of the leaf too.


When I saw this initially, I thought maybe edema, or mechanical damage, but I couldn't find anything that talked about edema even happening on Dieffenbachia, much less an illustration of it, and anyway the environment would seem to be wrong for edema, since as far as I can tell, the environmental conditions are normal indoor temperatures and humidity.

My own plants have bumps like this on the midribs of some of the leaves, which I assume is mechanical damage of some kind (I've seen the same thing on my Anthurium "hookeri" and Zamioculcas zamiifolia), but in those cases, I already know the plant's been banged around a little, and the bumps are centered on the midribs and stems (particularly in spots where the leaf or stem has been bent, twisted, or stretched) and don't appear on other parts of the leaf. The reader says that the plant has not sustained any mechanical injuries while this has been happening, nor are there pets that might be causing this.




The reader also reports that the new growth is pale, yellowish, and sometimes shriveled, with margin burns on some of the leaves. (I didn't really see this in the photos, but bad-looking leaves could have been groomed off, I suppose.)

This has apparently been happening since spring, and is accelerating as it goes on.


There might be something like an insect or mite on the leaves, but it's hard to tell for sure; it could be dust or water spots. There's no webbing or stippling like one would expect from spider mites, and the specks don't look big enough to be aphids. The color and size is right for maybe an early mealybug infestation, but mealybugs don't cause leaf swelling and margin burn, in my experience. Thrips might leave streaky brown spots like this, but they wouldn't cause leaf swelling, and they're not known to be a particular problem for dieffs.

I did an on-line search for dieffenbachias with broad mites or cyclamen mites (which I at least know can cause weirdly distorted foliage and a dusty appearance), but didn't come up with anything there: if they infest dieffs, it must not happen very often. (Also, my understanding is that cyclamen/broad mite damage is mostly the result of the mites feeding on the foliage while it's still developing, not something they do to mature, developed leaves, as in this case.)

So I am stumped. Not only do I not know how to fix the problem, I don't even have any good theories about what the problem is. So I'm hoping someone else might have some theories. Even wild guesses would be better than nothing, at this point.

I asked the reader a few questions, hoping to find support for one of my theories (didn't get any), and the Q&A is below:

-

Has anything fallen on the plant within the last few months, or has the plant itself been knocked over?
NO. I really am careful with them and I learned to give them time alone :)

Do you have a cat that might like to bat at the leaves, or is there anything else in the house that might pull at or twist the leaves sometimes?
NO ...and I'm a dog person :)

Is it in a spot where a lot of people passing by the plant would brush up against it?
NO, it's on a shelf in a dead-end balcony.

Have you had the plant for a long time, or is it fairly new?
Fairly new, I think this is the second year I got it as a little-thin-young stem, and the first year it grew thicker and stronger after repotting the upper-stronger part of the original plant.

Has it been exposed to any extremes in temperature?
Yes, I think so. There were some days last month when temperature approached 40C - 104F, but the problems started before that.

Does it stay inside year-round, or do you put it outside for part of the year?
Only in the closed balcony. No low temperatures in the winter.

Do you leave windows open during part of the year, and if so are the windows screened?
Yes, but not wide open. There is only glass-filtered sun, and yes I use shades when sun gets too strong (3-4 hours in the second part of the day).

How long ago did you first notice it, and has it gotten worse, better, or stayed the same since then?
This sping. At first there were only few bumps and small. Now there are present on almost every leafs (especially the old and mature ones) and seem to grow steadily.
The general aspect of the plant is worsening. Leaves wither and partially coil, the color is paler and yellowish, and almost all old leaves developed on their brims yellow-brown dead areas. (see the pic in the message before).

My impression is that there is a systemic problem that affect the whole plant. Something metabolic. Coming from an infection or infestation or the soil.
I have to mention that I used universal solid fertilizer from COMPO. One stick, once (made in Germany).

-

Any of this ring any bells? Anybody?

Question for the Hive Mind: Large-Seeded Plant

Another plant ID question from e-mail. I'm pretty sure I've seen this plant on-line somewhere -- the enormous green seed is pretty distinctive -- but I couldn't come up with a name, if I ever knew the name in the first place.

So does anybody have any leads? I'm told the seed came from China, if that helps anybody. Pictures may need to be opened in a separate window to view detail.

How to Deal With Plants Which Have Been Chilled

I occasionally get e-mails from people who want to know what to do for plants that have been accidentally exposed to too-cold temperatures. Maybe they've picked up a plant that was abandoned next to a dumpster in a snowstorm, maybe they forgot to bring it in off the porch in the fall, that sort of thing. And it's occurred to me that I didn't already have a post about this, so maybe it would be worth writing one, since whenever I'm asked I wind up having to write a whole big thing from scratch.

The problem is, there's very little to say about this situation. There is no special fertilizer you can apply to reverse cold damage, and keeping the plant extra-warm for a while isn't going to help either. You pretty much just have to give the plant whatever care it would ordinarily prefer (or maybe slightly drier than it would usually prefer, if you think there may be root damage) and wait to see what it does. Sometimes plants will surprise you: I had a jade plant (Crassula ovata) once that was accidentally left outside, in Iowa, through I think mid- to late December. It was covered in snow when I saw it and brought it in, but it recovered and went on for several more years anyway.

I didn't have any plant photos of plants being exposed to cold, but I did have a photo of a dog being exposed to cold. I figure since there was no Sheba/Nina picture on Saturday because of hiatus, probably nobody would mind a late one.
Even in situations where it's clear the plant has been badly damaged, cold usually harms the extremities -- the tips of branches, the topmost leaves -- most severely. So, one can often just cut branches back to undamaged tissue and the plant will sprout new growth. (The resultant plant won't be as big and pretty as it was, but given enough time, it can come back.) Also anything that's obviously dead (black, crispy, mushy) can be cut off: whether it's an aesthetic improvement or not, those parts weren't going to spring back to life anyway, so you might as well.

Aside from those few things, though, mostly you just have to wait and see how bad it's going to be. And, obviously, not do it again. Within two or three months (probably sooner), whatever is going to happen will have happened, and you can decide what to do from there.

Question for the Hive Mind: Reader NOID

A reader has, once again, managed to stump me on a plant ID question. This particular plant:

• was originally purchased via an ad in Town and Country
• has been around for several years
• blooms "all the time."

My only guess is that maybe the plant is in the Malvaceae -- that pistil (?) sticking out of the flower looks a lot like certain Abutilon and Hibiscus varieties I've seen. Though the leaves completely don't match.


So how about it? Even if you don't know a precise species or variety, confirming a family or genus would still be helpful in tracking it down.

Question for the Hive Mind: NOID strange flower

I got an e-mail last Friday that read, in part,

. . . do you have an idea what the plant in the attached pictures might be? It was given to me by a friend, who is quite certain that the plant salesman described it as a haiacanthus, and that its Dutch name is poederdons ('powder puff'). However, a plant listening to these names (in any spelling variety) does not seem to exist in the internets.

The question was accompanied by five photos, three of which are below. They'll all blow up much larger if opened in a separate window.




As the e-mailer says, there's nothing by the name Haiacanthus on-line, nor did trying variations on the spelling help. The only similar flowers I could think of were for stuff like Acacia, Mimosa, and Calliandra, and they all have pinnate leaves, so I don't think that's the right neighborhood to be trying.

So I bring it to the readers. Does anyone know what this is, or know of any succulents or cauduciforms (it looks like a caudex-former to me, anyway) that have flowers like this? 'Cause I am completely stumped.

UPDATE: Has been identified as Haemanthus albiflos in comments. I would never have come up with that on my own in a year of Googling (though I did think at one point that maybe it could be in the Amaryllidaceae, because of the leaves, I didn't follow up on it), and now I want one. Added it to the want list in the sidebar and everything.

Thanks to Don, John de la Parra, and College Gardener!

Question for the Hive Mind: Dahlia NOID

A PATSP reader writes,

I recently found your website while looking for growing information on some cacti- but after browsing through many past posts, I noticed that you and your readers help a lot of people with various plant ID. I fell in love with a Dahlia [in] a public garden about a year ago, and have not been able to figure out what kind it is. I was hoping someone might recognize it and know what it is called! It is a huge blossom, probably about 10-12” wide if I remember correctly. Very beautiful, rich jewel tone pink. The blossom seems to face downward, but there are so many frilly, wavy petals it all looks like a big messy ball. I have attached pictures (the last picture is of a soon-to-open bud), and greatly thank you in advance for your help!

Anybody have any guesses? Or know of any good Dahlia-centric sites that might be useful?

Question for the Hive Mind: two different orange-flowering NOIDs

Got an e-mail last night from someone interested in an ID for this plant, which was spotted in a Northern Minnesota state park three or four years ago. The photo isn't the clearest (it should help to open it in a separate window), but you should still be able to make out the main features: low rosette of leaves, prickly/hairy flower stalk and leaves, red-orange flower with lots of yellow stamens.


I'm fairly certain I haven't seen this growing as a weed or wildflower anywhere; I'm less sure whether it might have been something we had for sale at the garden center. All of that was sort of a blur at the time, and it's even more so after a year away.

And then as long as we're here, I've got another orange NOID for you. This second plant is one I saw growing in someone's yard recently. I'm pretty sure it's there deliberately. It seems familiar, somehow, but yet it's not ringing any of the I-used-to-sell-those bells for me.

Question for the Hive Mind: Philodendron bipinnatifidum

Got a question at the Philodendron bipinnatifidum profile that I am unable to answer. If anybody knows, please answer here or at the profile (though I'll have to approve comments at the profile, so they'll post more slowly).

Elle wants to know:

I had several large philodendron outgrowing their pots. I had some landscaping done and asked the fellas to plant them in the ground. Well....I think they just dug and stuck, without supplementing my soil which is clay so think I could build and addition to my house with it.

My question is: Should I dig them back up and add better soil? or can I add heaps of compost (horse manure and sawdust + heat composted) to the base of the plant? I'd be so sad to have killed these once beautiful plants. (It's been a couple of weeks and they're looking a little droopy and brownish.)

Repotting Questions (With Answers!), Part II

Now for the thrilling conclusion to my two-part repotting series. Those who missed part I (primarily about when to repot, and types of pots) may wish to check it out first, but it's not necessary.

What kind of potting mix is best to use, when repotting a plant?

Ball Professional Growing Mix, package. Ball also sells (at least around here) bags that are one-half and one-quarter this size, which have way more colorful packaging; the mix appears to be basically the same either way, though.
Well, I've told you before what I use: Ball's Professional Growing Mix. (I recently found a source that's 25% less expensive than the store where I used to work: the ex-job charges $24 for the 2.9 cubic foot (79 L) bag, and Washington GardenDecor and Greenhouses, in Washington, IA, only charges $18! This is incredibly exciting for me.) This is primarily composted bark (about 45-55%), with some peat moss (looks like about 30%), and a few miscellaneous other things. Often, and especially for rot-prone succulent plants, I mix in some perlite (a white expanded rock used to lighten and aerate soil mixes) or "aquatic soil" (smallish pieces of fired clay, which improve drainage).

If there is no Ball Mix available in your area (you're better off to try independent garden centers, as opposed to large chains like Lowe's or Home Depot), look for something with more composted bark and less peat -- the breakdown of what's gone into the mix should be listed somewhere on the package, though actual numbers may or may not be present. In a pinch, mixes saying they're good for cacti and succulents tend to be okay for houseplants. (The actual houseplant soils tend to be too wet, but the faster-drying, faster-draining cactus mixes are better, and sometimes that's as good as you can get.)

Epiphytic plants like bromeliads and orchids are harder to generalize about, but Ball mix plus some unchopped sphagnum moss works pretty well for bromeliads, and for orchids I'm probably not the person to ask, but the pre-bagged orchid mixes containing lots of large chunks of bark seem to be adequate, at least.

Do not use topsoil (more or less equivalent to garden soil). Even a little. Topsoil is extremely bad for container-grown indoor plants. Even if all the other gardeners are doing it. Even if they say they won't be your friend anymore unless you do it. Just say no.

Packaging of the "aquatic soil" I use. One may also use other brands (some are made of volcanic rock instead), other crushed clay products like Turface, aquarium gravel, very coarse sand, or certain "bonsai soils." Anything that's not going to dissolve when you water, can't hold a lot of moisture, and is made of particles which are at least 3-4 mm (about a tenth of an inch) across. The main advantage of this particular brand is that it's pretty cheap, and a lot of places carry it.
What about something like Miracle Gro?
I do not recommend Miracle Gro potting mix for anything, though if it's what you have already, it can be made somewhat more useful by mixing in perlite and/or aquatic soil. 2 parts Miracle Gro to 1 part perlite works reasonably well for most tropical plants. (Tropicals which are sensitive to fluoride do better with something besides perlite added: perlite generally contains some fluoride.) For plants which are prone to rot if they stay wet too long, like a lot of cacti and succulents, or tropicals which are fluoride-sensitive, I'd recommend something more like 3 parts Miracle Gro to 1 part aquatic soil to 1 part perlite, or 3 parts Miracle Gro to 1 part aquatic soil. Those are not tremendous improvements, however, and if you're buying aquatic soil and perlite already then you may as well just break down and buy some soil that will work, rather than spending the money and labor trying to fix the Miracle Gro.¹

Does potting soil go bad? Like, if I have a bag of potting mix I bought three years ago and never used, can I still use it, or do I need to throw it out and buy a new bag?

You can probably still use it. Soil that has been stored in a dry location should be fine. I wouldn't use soil that's been flooded or rained on (the plastic bags in which potting mixes are sold almost always have holes in them, and soil that has cycled between wet and dry will break down faster), but if it's stayed dry and looks and feels more or less normal, you should be fine.

Can you keep recycling soil forever so long as you continue to add nutrients (fertilizer), or does it eventually go bad and need to be thrown out?

It eventually breaks down to the point where it needs to be thrown out. Organic material like peat and bark slowly deteriorates into small pieces that pack tightly around roots. Inorganic material, like gravel and sand, can be saved and re-used almost forever, in theory (it does break into smaller pieces, but it takes a lot longer), but I think this is probably not worth the time it would take to separate.

You should suspect soil breakdown when a plant you've had for a long time without repotting, which always did well previously, starts going yellow, or yellow with green veins. There are nutritional deficiencies that will cause this color change as well, but soil breakdown has been the cause of yellowing in a few of my plants now (Strelitzia nicolai, Dracaena deremensis 'Warneckei,' Asplundia 'Jungle Drum'), and the odds are good that a repotting will also fix whatever trace element deficiencies are present.

I've seen products in the garden centers that advertise "gel crystals" that hold water extra-long in soil. Are these good to use in the soil for houseplants?

No.

That's it? Just, "no?"

Um. No, no, no?

They don't serve any real purpose for houseplants. They won't help, and they might hurt houseplants by keeping them too wet. They're more useful in outdoor container plantings, which dry out quickly in the wind and sun, but indoors, potting mixes are usually too water-retentive as it is. It really doesn't do you any good to keep the plants wetter longer.

Growing plants in nothing but these "crystals" is also done sometimes, and I admit, the effect can be kind of interesting, in a glass container. This is best suited for plants which can be grown indefinitely in water, like Tradescantia pallida, Syngonium podophyllum, Dracaena sanderiana, etc.

Still, there are some concerns about long-term toxicity of these products: the polymer used (polyacrylamide) is safe on its own, as far as anybody can tell, but it does decompose, and some of the decomposition products may pose long-term environmental problems. (.pdf) This would be forgivable, in a risk/benefit kind of way, if there were some huge benefit to growing plants in polyacrylamide gel as opposed to a regular potting mix, but it doesn't seem to. And it's not as though there's a shortage of things to plant plants in. After all, potting soil is cheaper, also holds water, plants seem to like it, and doesn't turn into poison in 5-10 years. So.

When repotting, do you have to put rocks, clay shards, or some other material in the bottom of the pot first, for drainage?

No. I used to do that, but now I don't think it serves any useful purpose beyond making one feel frugal for recycling broken pots. I'm told that there are hints that it may actually impede drainage in container-grown plants, though I haven't actually tried to find any such evidence.

How much soil should I put in? How do I, you know, actually do a repotting?

If you're moving a plant up a size, from a 6-inch azalea pot to an 8-inch azalea pot, start with about an inch and a half of new soil in the bottom of the pot. Set the plant's root ball down in the center of the new pot, and then fill in soil around it.² Pack it down with your fingers -- if it's too loosely packed, the plant may tip sideways later, when the potting soil settles, or the new soil may compact, leaving you with the raised circle of the old root ball sticking half an inch above the rest of the soil in the pot. (If that happens, just add more soil until the level is even. It's not a big deal.)

The procedure is similar for root balls that are irregularly-shaped: you try to dig a hole the approximate size and shape of the rootball, set it in, and then pack dirt around it.

Usually, the final soil level should be half an inch to an inch (1.3-2.5 cm) below the rim of the pot, though nothing particularly bad will happen to you if it's lower than that; it'll just look weird. If the final soil level is higher than that, you'll have trouble watering from the top in the future, so you may want to do it over.

Finally, in most cases, you'll want to water the plant in. This is different from watering a plant only insofar as regular watering is usually faster -- a newly-repotted plant's soil is sometimes a little water-repellent, and needs a bit of time to moisten; water may also percolate through the soil now that there's more of it. If the soil settles significantly, you may need to add more. Two situations in which you do not necessarily want to water in right away: 1) if the plant's old rootball was already really wet when you repotted it, 2) if you think you might have injured the plant in the process of repotting (especially an issue with succulents and cacti).

Stenocereus thurberi. They're pointy and un-fun to repot.
Do you have any tips for repotting very large or sharp plants?

Indeed I do. My method for large, floppy plants is here (using a Boston fern as the example plant), and for large, sharp plants, you can try this post, which is similar but uses a screw pine (Pandanus veitchii) as the example.

When repotting cacti and spiny Euphorbias, gloves are often very helpful, though I have only encountered one or two pairs in my lifetime that long, sharp spines couldn't still poke through, and sadly, neither pair belonged to me personally. In a pinch, a newspaper, towel, or paper towel can be used to hold the cactus steady with one hand while the other firms the soil around the roots. I also hear that people can do wonderful things with tongs sometimes.

Euphorbia trigona.
Similar stuff applies to Opuntias, though because of their evil, evil glochids, I wouldn't even attempt repotting them without pretty hardcore gloves. And long sleeves might not be a bad idea either.³ Hate, hate, hate Opuntias.

For extremely large plants, it sometimes helps to have a second person around to tell you when the plant is properly vertical, and/or to help with the lifting and maneuvering. And avoid the ceiling fans.

What about for very fragile plants like Schlumbergera or Sedum morganianum?

Sedum morganianum. The leaves are pretty loosely attached, and fall off easily. Detached leaves can be used to start new plants, though, if set on top of a lean, fast-draining potting mix in a sunny spot and watered occasionally.
Not really. I have so far managed to get through life without ever having to repot a Sedum morganianum, and with Schlumbergera, I think it's best to just go slowly, assume in advance that some pieces will fall off, and be ready to try rooting them as new plants. (If any readers have suggestions on this one, leave them in comments and I'll edit the post as necessary.)

So what have I left unanswered? Anybody?

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¹ Why is Miracle Gro bad? The main reason is that it's got a high peat content, and peat absorbs a lot of water, so it dries out very slowly. Good for an outdoor container, maybe, but not a quality you want for a houseplant. Also, when peat finally does dry out, it starts to repel water, and then is hard to get wet again. So for houseplant purposes, often the wet is too wet and the dry is too dry, is basically what I'm saying. Some plants would grow okay in Miracle Gro; I've used it myself in the past for a few things just because I didn't know any better, but the water-repellency annoyed me even then.
A second problem is that Miracle Gro, unlike the Ball potting mix, is not sterilized before shipping, which means that it may contain mold or mushroom spores, insect eggs, or other undesirable things. Mold and mushroom spores are not as big of a problem as you might think, at least not for the plant. (Some molds look really repulsive, and some people may be allergic or whatever, but in most cases it's only an aesthetic issue, not a health issue, and the plant itself usually doesn't care.)
As for insect-eggs, Miracle Gro always seems to bring me fungus gnats. Which, fungus gnats are frightening for novice houseplant growers, but they typically don't harm the plants. More of an annoyance than a problem. Still, given the option, most of us would choose not to have fungus gnats, and they're very nearly a sure thing, in my experience, if you buy Miracle Gro. So I don't recommend MG for anything.
Miracle Gro makes a number of variations on the basic mix; I don't know whether any of them are any better for houseplants. But I would be surprised.
² In some cases, I also try to loosen the roots from the root ball before planting, though I don't always. If I can pull apart the mass of roots, in a badly rootbound plant, I try to do so, but if the situation is bad enough, that's often not possible, so I just plunk it in and hope for the best. With some plants, like Ficus benjamina and Spathiphyllum, I do get kind of rough trying to rip the roots apart from one another, because in my experience they're able to take it, and at least in the case of Ficus benjamina it appears to be good for the plant, stimulating new root growth.
³ Long sleeves are also a pretty good idea whenever you're repotting Euphorbias; many species have poisonous sap that can cause serious skin irritation, and it's a common enough thing for plants, especially plants like Euphorbia trigona (its shape is such that stems are very likely to poke one another in the process of repotting). Eye protection wouldn't be a terrible idea for Euphorbia tirucalli, either.

Repotting Questions (With Answers!), Part I

Today we have assorted answers to repotting-related questions that I've seen either on other sites or as search terms leading people to PATSP. Part II will be up on Friday.

Is it true that some plants prefer to be rootbound?

I really don't think so, though 1) it is maybe sometimes the case that the stress of being rootbound might encourage blooming for some plants, and 2) some kinds of plants mind being rootbound a lot less than others.

This is what we mean by "rootbound."
Do you have to repot new plants when you bring them home right away, or can it wait a while?

Depends on the plant. I always used to repot everything when I first got it home, because that's what my mom did. I don't do that anymore, because it's not always the case that they need it.

That being said, it is frequently the case that new plants will be potted in a mix which is mostly peat, and would benefit from being switched to something a little quicker-draining. So changing the soil and putting the plant back in the same pot is often a good idea, though I don't usually do that unless the original potting soil is terrible.¹

How do you know when a plant needs to be repotted?

Plants should be repotted when two of the following apply: they dry out quickly even though you saturated the root ball with water when you watered, the plant's roots are wrapped around and around the inside of the pot (you will have to knock the plant out of the pot to determine this), or there are roots growing out of the drainage holes.

Rootball of Callisia fragrans. This could probably go a little longer if it needed to, but if a rootball looks like this then you're probably good to go ahead and repot.
With plastic pots, sometimes trying to squeeze the root ball lightly through the pot can tell you something about how rootbound the plant has gotten: this is particularly the case with plants that have underground runners like Stromanthe sanguinea cvv., Maranta leuconeura cvv., Sansevieria trifasciata, or Rhapis excelsa.

Another indicator, which is not the most reliable but is another thing to watch for, is if you see exposed roots above the soil line. This is not entirely reliable because some plants naturally have aerial roots (Monstera deliciosa, Epipremnum aureum, Philodendron bipinnatifidum, Anthurium andraeanum cvv.) and others actually push themselves out of the ground over time, exposing roots (Pandanus is kind of famous for it, but also Chamaedorea metallica will do this), but still -- it's an indication that soil is breaking down and/or washing away.

Some exposed roots on a Breynia disticha; this might actually be normal for Breynia (I'm not sure), but it's what the kind of exposed roots I'm talking about would normally look like.
Even if older plants haven't outgrown their pot, they will generally need to have their soil replaced at least every couple years. This is because soil particles break down over time, and as the particles get smaller and smaller, they compact more and more tightly around the roots. Eventually, the particles can prevent air from getting to the roots altogether, suffocating them and leading to rot.

Every time I pick up the pot of a particular plant, there's a small pile of dirt at the drainage holes. It's composed of weirdly uniform-sized particles. Is this bad? Is dirt leaking out of the soil? Do I need to replace this? What's going on?

The saucer of my Araucaria bidwillii.
It's probably either an earthworm or a centipede in your potting mix.

Ohmigodohmigodohmigod what do I do?

Um . . . nothing?

But it's a BUG!

Yeah, so? It's not hurting anything.

But! They're GROSS!

I'm telling you, you don't have to do anything. The presence of an earthworm or centipede might cause the soil breakdown to happen faster than it otherwise would, and obviously if you're so squicked by the idea it's there that you can't sleep at night, then maybe you should dump the soil out and stick the plant back in the same pot with new soil. However, earthworms are after edible decomposing bits in the soil, and centipedes are looking for insects to eat: neither one is going to go after the plant itself. It'll be fine even if you leave them alone.

But I want them deeeeeaaaaad! And I don't want to touch them! Can't I just dump in some poison?

[rolls eyes] Okay, well, it's your karma.

If you must kill them, you can wait until the plant next needs to be watered, place the plant in a bucket, and slowly add water until the water level outside the pot is up to the soil level inside the pot. Anything that's living in your plant's soil will either claw its way to the top, where someone less squeamish than yourself can remove it, or it will fail to do so and eventually drown.

Don't make the plant sit in water any longer than it absolutely must: once you've dealt with the soil problems, get the plant out of the bucket and draining in a sink or bathtub or something. Plants can drown too.

When I repot, how do I know what size pot to use?

The usual rule of thumb is to go up by increments of one inch (2.5 cm) until you reach a five- or six-inch pot (13 or 15 cm), then go up in increments of two inches (5 cm) thereafter. So if your plant is in a 3-inch pot (7.6 cm), move it to a 4-inch (10 cm); if it's in a 6-inch (15 cm) pot, move it to an 8-inch (20 cm). This basic rule of thumb applies most of the time; there are also some special circumstances when you can jump more than two inches at once, which let's not get into those right now.

And how do I know what size a pot is?

[puzzled look]

Well, you measure it. Or look at the tag, or the underside of the pot. There's usually some indication. For round pots, the pot size is the diameter across the top. For square pots, the pot size is measured across the diagonal, not the length of a side like you'd expect. This means, among other things, that 3-inch square pots are slightly over 2 inches per side, and a 5-inch square pot is 3.5 inches on a side,² which even confuses people in the business sometimes.³

On triangular or otherwise oddly-shaped pots, I would assume that the longest side or diagonal you can find is the technical "size" of the pot, though this doesn't actually come up often enough to be worth spending a lot of time thinking about.

When repotting, what kind of pot is best? Should I use clay, plastic, ceramic, or what?

This depends a lot on the size and species of plant you're talking about. Clay pots dry out faster, because water can seep through and evaporate from the pores in the clay. Plastic and ceramic pots, on the other hand, tend to retain water longer. So plants like cacti and succulents, which are prone to rot if they stay too wet for too long, tend to be better off in clay, everything else being equal, while more drought-sensitive tropical plants are safer in plastic. Ceramic pots are more decorative, but are also more likely to lack drainage holes; they otherwise work like plastic.

For plants which are very small, both plastic and clay pots dry out quickly, so I generally use plastic regardless of which plant is involved. For very large plants, the center of the root ball tends to dry out very slowly, and this can be very bad for certain plants, so I try to use clay whenever I can, to speed drying. The disadvantage of this, of course, is that large clay pots are very expensive, easily broken, and extremely heavy.

Plants that are very tall and top-heavy for their pot size will benefit from the extra weight of a clay or ceramic. Plastic pots can be weighted down by adding a layer of rocks to the bottom or using a potting mix with added gravel, coarse sand, or "aquatic soil." (See Friday's post re: "aquatic soil.")

What's the difference between a standard pot and an azalea pot, and how do I know which one to use?

Standard pots are the same height as their diameter. A four-inch round standard pot is also four inches tall. Azalea pots are only 3/4 the height of their diameter, so a four-inch azalea pot is only three inches tall. The difference between them is really fairly minimal for most purposes.

I tend to favor azalea pots for their slightly lower center of gravity. (Plants get knocked over a lot here in the Subjunctive Botanical Gardens.) I do not recommend using pots that are taller and narrower than standard pots, or shallower and wider than azalea pots: the first are so top-heavy that you're just begging the plant to fall over, and the second are so shallow that tall plants like Sansevieria or Dieffenbachia may never be able to root themselves stably. One strong breeze and the plant falls over the pot edge and uproots itself.

Standard 4-inch plastic pot (orange, on left) and a 4-inch plastic azalea pot (green, right). The heights are not precisely 4 and 3 inches, but they're a little closer to it than this picture makes it look: part of the issue here is the angle from which the picture was taken.
Is it ever acceptable to put a plant in a pot that lacks drainage holes?

I don't know how to answer this question.

What do you mean? Yes or no, right?

I guess. But "acceptable" is a tricky word. I can't decide whether or not it's acceptable for you to do that. It doesn't actually matter to me. It's your plant. It'd be acceptable to me if you poured liquid nitrogen on it, if that's what you really wanted to do. Given the choice between a pot that has drainage holes and a pot that doesn't, the one with drainage holes is considerably more likely to still be home to a happy plant in a year. It's kinda up to you.

COMING UP ON FRIDAY: Choosing and amending a potting soil, adding clay shards for "drainage," tips for repotting particularly awkward (large, floppy, sharp, fragile) plants.

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¹ Some of the more recent plant purchases were succulents, which are fairly rot-prone as a group, and need quick-draining soil that isn't going to hold a lot of water or stay wet for a very long time -- and they were potted up in a mix that was mostly peat, which holds a lot of water and stays wet for a really long time. So I did repot them more or less immediately on arrival.
² More or less. Different plastics companies appear to define it differently. This 3-inch pot, for example, is only 3 inches across the diagonal at the fill line inside the pot, not across the actual top of the pot:

I also found one square pot in my collection that was 4.5 inches according to the code on the bottom, but 5.5 inches across the diagonal and 4 inches on a side, so I'm not sure what measurement they were using. But in general. Strict mathematical precision is not the point; the point is not to use a much larger pot, because a much larger pot is going to stay wet for a really long time, and this may affect the plant badly.
³ During my last purchase at my ex-job, the boss herself rang me up, and although I told her I was buying 3-inch cacti, and she saw the pots right there, she only charged me for 2-inch ones ($3.50 each instead of $4.95 each). And it's not because she was being nice to me or cutting me a deal. She's just never believed me about the diagonal thing, even though she can read what's stamped on the bottom of the pots, or get a ruler and measure, just as easily as I can. I didn't mention it at the time because I didn't know that's what she'd done until I was looking at the receipt in the car. Though if I'd noticed at the store, I probably still wouldn't have said anything.

Question for the Hive Mind: Cordyline fruticosa 'Kiwi'

I got an e-mail a couple weeks ago from someone who wanted to know if I could tell what was going on with her newish Cordyline fruticosa 'Kiwi.' I did answer, but didn't have a lot of confidence in my answer, and offered to post the photos here and get some second/third/fourth/etc. opinions. So here's the situation.


The plant is getting holes in the leaves which forming in straight lines, in no particular spot on the leaves. Also, the leaf tips are drying out and turning brown (though the brown tips were cut off before these pictures were taken), and some of the leaves are getting brownish patches.

There are no visible signs of mites or other bugs. There are a few whitish spots on the underside of the leaves, but they don't wipe off.


The plant was purchased about three or four weeks ago. It did get repotted shortly after arriving. The home does have a cat and dog, but they are not near the plant, nor is the plant in a high-traffic spot for people.

They're in Tucson, AZ. Another plant at the same store (unclear about whether it's also a Cordyline or whether it's another kind of plant) had the same problem.

The plant is continuing to do the same things even after a few weeks at the house, so it's probably not entirely something the store did (though it could be partly, maybe).


These are the only pictures I've got.

I'll tell what my guess was after we get a few people making guesses of their own, because I don't want to bias people's guesses. I'm sort of hoping that someone will say oh sure, I know exactly what that is; I see it all the time, but everybody should feel free to speculate wildly.

Infrequently Asked Question: 550ish plants? How?

I have, on occasion, been asked how I can manage to fit so many houseplants into my living space. It's a fair question. The answer hasn't always been clear to me, either. I've been thinking about it again lately because a reader asked (by e-mail) a couple weeks ago, and it occurred to me that this is something I hadn't addressed yet on the blog, exactly how I manage to stack plant upon plant in a way that enabled me to get 550 or so in a two-bedroom apartment.

There are three key components of my set-up. The first is simple and obvious: small plants take up less room than large ones. If you just want to impress people with how many plants you have, get a bunch of 3- and 4-inch ones and call it a day. This isn't quite how I do it -- I think just by the amount of space they take up, my 6-inch plants are probably the bulk of the collection -- but there are quite a few 3s and 4s, especially among the succulents.

The second part is: four-foot shop lights. They're easy to find, and can be had for about $10 if you shop around a little. Four-foot fluorescent bulbs are not cheap, but they also last for a long time,¹ and fluorescent light is perfectly adequate for a lot of different plants as long as it's not too far away from them, so they're cost-effective in the long run.

African violets, Saintpaulia ionantha cvv. African violets are often grown under all-artificial light.
(I am not, by the way, a fan of the special "plant lights," formulated specially to produce extra-large amounts of the red and blue wavelengths plants need. They're outrageously expensive, for one thing, and I also don't like the unnatural purple color. Regular cool white and warm white bulbs² do just fine.)

The third part, and arguably the most important from a plant-density angle, is: shelving.

I use wire shelves. I don't really have a good name for the particular product (The last boxes I bought said they contained "black wire storage," which amused me: finally! A place to stick all those annoying black wires!), but they're sold in a lot of different places: I've seen them at Lowe's, Menards, Target, etc. There are often a range of different sizes: usually a given company's shelves will fit together regardless of whether you have them all the same size or not, but it's worth paying attention to. (You should definitely try to make sure you're getting all the same color, and from the same manufacturer: this will save you trouble later. I've seen them in black, chrome, and white.) I recommend six-foot tall (72"), for the simple reason that six-foot is usually as tall as they get, and if maximum plant density is a goal, more height is better than less height. The widths vary, though they're usually three-foot (36") or four-foot (48") wide. Four foot is better if you're going with the standard four-foot shop lights. Three-foot may be more suitable for a window, if you're relying on natural light and don't have to worry about fitting shop lights on there.


As packaged and displayed, these shelving units are usually just four poles and four or five shelves, which can be placed more or less anywhere on the poles, so you can adjust the heights of the shelves to your individual needs. I've found that sometimes I don't want to use all the shelves they include: five shelves over a span of six feet means that the average distance between shelves is only 5/6 foot, or ten inches. You might be surprised at how few of your houseplants are under ten inches tall. However, if you buy two sets at once, there's a trick you can use to get much more usable space, which is that you can connect the two sets of shelves with a third set in between:


This way, instead of having ten shelves that are all only 10 inches apart on average, you have ten shelves that are all 21.6 inches apart (72*3/10) on average, which is much more useful spacing for your average houseplant. You can continue this if you want to, and buy a third set of shelves, and connect them twice across the gaps, which puts your spacing at 24 inches apart (72*5/15), and if you really need additional height you can always just leave out some of the shelves that come with the set.

If you run out of wall and need to turn a corner, you can connect two lines of shelves by having both sets share one pole. I'm not sure how to describe it in words, but maybe this picture will illustrate well enough:


The circled pole is shared by a long set of shelves going off to the right of the picture, and by a three-foot shelf going to the left. A fun thing about this is that if I'm really, really slow and careful about it, the shelves on the left can be rotated around the pole to get the two large cacti in the corner out to be watered or whatever, and then swung back into place when they're done, thus leaving the corner still, in theory, usable.

Anyway. So this was the basic set-up I had in three different spots in the apartment, when we lived there. You can, if you are so inclined, try to suspend shop lights from underneath each shelf, but it's easier to just lay the shop lights on top of each shelf, pointing downward through the shelf they're resting on to light the plantsbelow. In some cases, I took advantage of that by placing small cuttings on the back of the shop lights, using the light above the plants for intense illumination and the light below them for bottom heat. It worked better for some things than for others, of course, but when it worked, it worked amazingly well.

The lights can then all be plugged into power strips, and the power strips placed on timers, to turn on sets of lights all at once.

One bad thing about the shelves is that it can be hard to get smaller pots to balance properly: you have to place a three-inch pot pretty carefully on wires that are an inch apart. I eventually resorted to getting some flat plastic (acrylic? polycarbonate?) sheets to lay down on top. They don't have to be especially strong, just flat. The air circulation suffers, but you have less dirt raining down on the floor, which is a plus.

It's also very easy for plants to fall over the back edge of a shelf, so I find it works best when I have one of these up against a wall, with the lights in back. Though putting them close to, but not touching, windows did work in the apartment in a few spots, and sometimes you have to do what you have to do.

The basement shelves. These are possibly going to have to be redone later, because I'm not happy with the range of heights I got out of them and the distribution of warm and cool bulbs, but the general idea should be more or less clear by now.
What does a set-up like all this cost? Well, say you're going to buy two sets of 6-foot tall, 4-foot wide³ wire storage units and connect the fifteen shelves you get from that as far as they'll go, and light the backs of every shelf you can light the back of. Target often has these units available for about $60 each,⁴ so that's $120, and then if you're setting up like in my amateurish sketch above, you can light nine of the shelves (the very lowest one is too close to the floor to get any plants under, so there's no point in lighting it). That means nine shop lights and eighteen fluorescent bulbs. Figure $10 each for shop lights, and figure a box of twelve cool white bulbs costs $25 and a box of twelve warm white bulbs costs $35, and that a light timer can be had for $4 and a power strip costs $8:

$120 shelving units
$90 shop lights
$25 warm white bulbs
$35 cool white bulbs
$24 power strips
+$12 light timers
$306 total

And what have you gotten for the $306? Well, you have ten shelves plants can go on, plus two sections of floor underneath the shelves where plants could also go. Each shelf is roughly 1.5 x 4 feet, or 6 square feet, so that gives you 72 square feet of space, except that the shop lights take up about (9*4*0.4) 14.4 square feet of that so you're really only getting (72-14.4) 57.6 square feet of space.⁵ And then that's only a net gain of (57.6-18) 39.6 square feet, because the whole set-up takes up 18 square feet of floor space that were there previously.

So 39.6 new square feet of growing space for $306: it's $7.73 per square foot. Pricey, but: all the new space, plus the floor area it takes up, is well-lit, higher-humidity (because the plants are closer together) space with good air circulation (wire doesn't block airflow), it's vastly cheaper than the equivalent 6'x6' greenhouse or room addition would be, you won't have to buy fluorescent bulbs for a while, the heights of the shelves can be adjusted as plants grow, and it doesn't add to your heating bill as dramatically as adding a room would. (It does use some additional electricity, but not really so much that you'd notice a difference unless you get really crazy with it.)

I was getting, on average, about 12-18 plants per shelf back in the apartment, so this would be space for approximately 135 plants, or more than that if you pick up more 3- and 4-inch plants like I recommended.

My mini-greenhouse. If you desperately needed to have a very, very high-humidity area for propagation or whatever, you could probably wrap a shelf or two in clear plastic more or less like this and get something functional, if not pretty.
Set up another three units like this in another three rooms, and you have (57.6*4) 230 square feet of plant-growing space plus another 40 square feet of bottom-heat propagation space, room for 540 plants, and you've spent about $1224. The best part of this is that you can buy new shelves one unit at a time, so it's $1224, but in lots of little chunks over a long period. Unless you're really getting serious about propagation, or planning to buy a very large number of plants all at once, you can spend the cash in dribs and drabs, which makes it all sort of affordable. Or at least the kind of expensive you don't notice while it's happening.

The shelves are also moderately good bookshelves or aquarium stands,⁶ if you change your mind later and decide that you'd rather not keep so many plants. I mean, they're a decent long-term investment on their own.

So now you know how I crammed them all in. Is it an example to be emulated?⁷ I suppose depends on your priorities.

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¹ A lot of people will advise you to change bulbs after a year, even if they've not burnt-out. I know this is something the hard-core, competitive African violet growers do, for example. It is unquestionably the case that light output of fluorescent lights drops over time, and I can definitely see how this might become relevant if one were trying to create very standardized, uniform plants, or if one were trying to grow plants with very exacting light requirements. I don't worry about it so much, personally, because as I mentioned, fluorescent bulbs are not cheap. Also, the sites recommending this never really say what you're supposed to do with a whole bunch of dim, year-old fluorescent bulbs.
² One recommendation I've seen, that I do like, is to mix one cool white (more blue) bulb with one warm white (more red) in each fixture. I honestly don't think the plants care, but the resulting color of light is a little more natural. Also, if you're worried about the red/blue wavelengths thing, mixing warm and cool bulbs would be a good way to feel like you're doing something about this without going bankrupt or turning your home lavender. I don't personally mix warm and cool lights in all of my light fixtures, because, again, I don't think the plants care that much, but in the cases where I have mixed the colors, I like the color of the light better, personally.
³ In most cases, the depth of the shelves is 18 inches, though other sizes are available. It really doesn't matter as long as you're careful not to buy different depths. You can mix three-foot-wide shelves with four-foot-wide shelves easily enough, and if you plan it properly you can mix different heights, too. But depths you have to match up correctly.
⁴ (though not always: right now their web site says $150: that's not typical, or even heard of, in my experience. The website's price structure is clearly different from that of the brick and mortar stores.)
⁵ Plus the backs of six of those shop lights could be used as bottom-heat, top-light propagation areas, so that's (6*4*0.4) 9.6 square feet of propagation area, in theory.
⁶ Mine were originally used as bookshelves; the plants didn't begin to crowd out the books until I'd had the shelves for eight years, and by then a lot of the books had moved on anyway. I'm not 100% certain about using them as aquarium stands: I forget exactly what the maximum weight capacity is supposed to be. Enough to have them full of books, in any case. They should certainly be adequate for a ten-gallon aquarium full of water, or a twenty-gallon terrarium, on each shelf. One minor drawback: the wires do bounce a little bit when heavy things are dropped on them, so they may not be quite as stable as you'd want: that could probably be dealt with by adding a sheet of plastic or a piece of plywood or something. Also, shop lights don't have quite as many alternate applications as the shelves themselves do, so you would still be stuck with those. But your shop, if you have a shop, would be blindingly bright.
⁷ No. It is probably not.