Friday, May 27, 2011

Pretty picture: Cattleya Confetti x C. aurantiaca


Again from the orchid show last March, and again with a Cattleya. They really are terribly photogenic, and y'all know I have a thing for orange flowers.

I'm feeling kinda down on orchids lately: the Oncidium I bought last December had been doing better than any other orchid I've ever owned, until about three weeks ago, and then it started throwing leaves everywhere and won't stop. The Potinaras and Sophrolaeliocattleya aren't throwing leaves, but they're not growing, either. This is how pretty much all my orchid purchases go, as far back as I've been trying to grow orchids. I'm getting sick of it. Either I'm going to have to find better spots for them to live -- which will be difficult, since space is extremely limited, and the best spots are already occupied by more appreciative plants -- or PATSP is about to have a Summer Orchid Giveaway.


13 comments:

Pat said...

What fertiliser do you use?

mr_subjunctive said...

It was Osmocote 14-14-14 w/o trace elements, but I've switched to Miracle Gro 24-8-16 with trace elements.

stefanogiovannini said...

Probably epiphytic orchids in bark or similar can not uptake urea based nitrogen. Better use a fertilizer like Better-Grow that are formulated for orchids. My Cattleyas seem to be growing ok. I put some closeout I got for a dollar on my roof and are growing nicely. Something easy to grow that grows fast is the Bc. Kosh Wallis (or is it Wallace). Found it at Lowes in a bag. It has Brassavola kind of leaves that turn purple in the sun. Oncidium Twinkle, Onc. ornithorynchum, Miltomidium Rosy Sunset and the rambling Miltonia spectabilis (this one in a shallow bonsai pot with sphagnum and coco chips) are all growing easily and quickly. I think more light = more watering -> faster growth.

Anonymous said...

I vote for the orchid giveaway!

Derek said...

Agreed with stefanogiovannini - try an orchid-specific fertilizer, and use very little of it. I only fertilize mine once in a while. Also, orchids really like air movement - do you have a fan going? And finally: when the leaves fall off, are they yellow or black? Black means too damp, yellow means ... something else.

Also: What medium are they in? If they're in a bark combo that holds little water, they need to be watered or misted frequently. It's basically impossible to overwater since the bark holds so little water. But if they're in a damp moss, they can easily drown and rot - water only when the moss is dry to the touch, every two weeks or so.

And if you ever want to send some to "the farm", you've got my address. ;-)

Sentient Meat said...

Yes, they say bark and other non-soil media lack the microbial action which converts urea (the cheapest form of nitrogen, and the majority of N in Miracle Gro) into a nitrogen form usable by roots.

I don't know how much advice I should be giving about orchids. My succulents are doing great, but most of my orchids died. (Granted, they came to me with bugs, and most were rescues from a friend who had to walk away from his mortgage. But still it wasn't fun to watch 90% of them die under my care.)

mr_subjunctive said...

Derek:

For the most part, the leaves that fall off are yellow. Certainly all the leaves on the Oncidium that's crashing are yellow.

Also the problem orchids don't have good air circulation, for the most part, while the still-stubborn-but-at-least-growing-sometimes ones are in the plant room, where there's a ceiling fan that's on 24/7/365. Except for the Paphiopedilum, which should have decent air circulation but still sucks.

The medium depends on the plant; I have one in straight sphagnum, one in straight coco fiber, and one in a mixture of the two. (I ran out of coco fiber midway through the repotting process.)

If they have to be misted frequently, then we're going to have a giveaway. I don't have time for that shit.

stefanogiovannini / Derek:

Yes, the Miracle Gro label says the 24% nitrogen in the formula is 20.5% urea nitrogen, so that could be part of the explanation.

Sentient Meat:

I know the feeling. That batch of plants that included the Dyckia, that I wrote about a while back, is still dying off. The survival rate is now about 50% (down from 67%ish a week and a half ago). It's kind of awful.

Derek said...

So if yours are in moss/coir, then make sure you water only when they go totally dry. Overwatering is the #1 way people kill orchids. I once spoke with a grower who said that they put them in moss because they have to water much less that way, but the orchids are happier in bark with frequent watering.

If you wanna do a test, pick one of the sad orchids, depot it, remove the media, and check out the roots. If they're black/brown and squishy, your problem is rot, probably from too much moisture in the media. An orchid can recover from this if they're a fighter, but it's 50/50.

(BTW, this is also why the air movement is good for them, it helps the media dry out.)

If the roots look white/silver with green tips, they're totally healthy. Repot it in a fresh mix. I like to use a combo of a little Sphagnum to hold water, a little bark for the roots to grab, and a little Perlite to keep it airy. In general, the thicker the roots, the bigger the bark pieces. Last thing: The roots need air, so make sure to pot it in a pot with lots of holes in it. You can just punch holes in a plastic pot if you don't want to buy a special one.

One last thing: most orchids like it warm in spring/summer. If it ever gets into the 50s for them, that could explain the leaf dropping, too.

stefanogiovannini said...

coir will make Oncidiums and Cattleyas roots rot! roots need areation. Some grow Cattleyas in moss in clay pots. but it is tricky.

Moss is good for Bulbophyllums, but for Oncidiums I use a mix of coconut chips (not coir!) and maybe perlite and bark. I like also the stringy coconut fiber for some. I use often net pots inside a pot. Keeps humidity around the roots but lets the media dry.

Problem with coir and sphagnum is that the top will dry quickly and the center of the pot will stay soggy.

I often put a thin layer of sphagnum on top of the media.

anyway some orchids are OK with freezing temperatures, like a Laelia superbiens division I was given as a trade. Now it is on my roof exposed to wind and sun and growing great roots. With lots of light the orchid grows faster, you can water it more. I would put them outside. Now it is warm and humid. Probably leave them outside till october

Bom said...

This is why I haven't tried my hand at orchids. I feel they are too high maintenance although a friend of mine insists that they are quite easy to care for. If you are having troubles then I think it is best for me to just appreciate them at shows.

Pat said...

A problem with coir is that it adsorbs potassium and calcium at first so some plants suffer deficiency. After about two months it starts to break down and release the K and Ca which can cause toxicity due to the excess. The other problem for orchids is the lack of aeration.

stefanogiovannini said...

Some orchids grow great in coconut shells. Some Dendrobiums are easy easy.
I killed some but others are doing very good. Seedlings are harder.

Anonymous said...

After growing orchids on window sills, and some lightstands for years, I have slowly found this method for watering works best for me: Fill a bucket with 1/2 strength fertilizer in the warm water to the correct amount. (if you have bugs add some Safer's Soap or Neem etc. drop or two of bleach for fungus or rot) Submerge the pot into the water so as to fill it to just cover the bark without floating it away, and let the bark soak in it for 10 to 15 minutes or so. This removes old salts each time, and the bark hydrates finally, and with a loose mix it is magic. Drain fully and put back into same spot with what they like. For the Cattleyas, I let them dry out in between watering in direct sun in Seattle which is different than elsewhere, paphs, not so much sun and keep a bit damper, and others not at all. They die from over watering, so take it easy and play by ear. I use off the shelf high nitrogen orchid fertilizer from a garage sale find.

Constant feed and as much light as you can give them without burning them as per variety is the key. They all like an outdoor vacation and such too, just be SURE your environment out there is warm enough at night or not too hot for the tender ones, shade and sun accordingly, getting them used to it of course. Those that need a chill to start to bloom stay out til late Sept or Oct depending. In this climate Cymbidiums can be out until it freezes or snows and then in until bloom is over and out as soon as possible.

Took me 15 years to listen to what people were telling me. Boy am I dense sometimes!

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