Monday, February 23, 2009

Work-related: Vermiculite (Schefflera propagation)

I was never a big fan of vermiculite until fairly recently. I didn't dislike vermiculite; I just never saw the point of using it for anything, because what could vermiculite do that perlite couldn't? It's too compact, and breaks down too fast, to be useful for lightening a heavy soil mix, and if you want to make a mix more moisture-retentive, there are a lot of simpler options. So vermiculite just seemed redundant.

But I have now discovered one area where vermiculite is far superior to perlite or anything else: starting cuttings of species that don't like to start from cuttings. We've gotten about 55-60% success with geraniums (as opposed to about 30%, maybe less, with direct-sticking cuttings into potting mix); we've gotten six or seven plantlets off of single Saintpaulia (African violet) leaves, repeatedly (as opposed to attempts that either fail completely or only produce one or two plantlets, from soil or water); and now this.

The story is that someone brought us a Schefflera arboricola they no longer wanted and told us to do whatever we liked with it, salvage, resell, whatever. WCW cut it to bits and planted about 25 cuttings in vermiculite, which on Saturday I sorted through the pieces and got five plants out that had rooted. 20% success may not sound that great, but this is the first time we've ever gotten Schefflera cuttings to do anything but die, and we've tried a number of times before.1

Not only that, but we weren't even trying terribly hard. A lot of our cuttings are just scraps of whatever that WCW or I think might be worth something, someday, but then we don't necessarily have the time to follow through with the care, so they get watered haphazardly, sometimes get moved around into bad locations, etc. With the above geraniums and African violets, we were making an effort to remember to water properly, but watering the Scheffleras was sort of an afterthought if it was ever a thought at all. So five of them making it, and not just making it but doing well (look at that rootball! And it wasn't even the most impressive one!), is kind of amazing given the circumstances.

Vermiculite: is there anything it can't do?


1 More from a waste-not-want-not mentality than any urgent need to have more Schefflera arboricolas. They do sell, but not fast enough that we're in danger of running out.
I don't even especially like the species. S. actinophylla is the more interesting plant to me, possibly because it was around when I was a kid and arboricola wasn't. They both suck compared to S. elegantissima, though elegantissima is not much to look at either, unless several plants are planted closely together.
In any case, now that I've seen this, I respect S. arboricola more, and I brought one of the cuttings home with me. We'll see if being around it makes me like the species better.


our friend Ben said...

This is just great, Mr. S.! Like you, I'd always thought of vermiculite as a benign moisture-retainer in soil mixes. Now you've inspired me! (But, er, not to try scheffleras. Ugh!) Thanks!!!

Darla said...

I will agree with Ben, never gave vermiculite much thought, perhaps I too will re-think it. This plants do look great!

Ivynettle said...

Really? 60% success with geraniums? Provided we're talking about the same plant, I've found them one of the easiest - I'd be in big trouble at work if I got anything less than 99%.

(I've stumbled across your blog recently while searching for the name of one of my Dracaenas, and I'm enjoying your posts a lot. :) )

Anonymous said...

Thanks for the the tip about using vermiculite to root Schefflera. I tried several times last summer to root cuttings, but they all died.


mr_subjunctive said...


You have to appreciate that we're really a retailer, not a grower. We try to start some of our own stuff, and extend what we've got through division and cuttings and what have you sometimes, but the impression I get is that until I started working there, nobody worried much about propagating, and people sort of regard my interest in, and enthusiasm for, propagation as weird. So yeah, only 60%, but I was starting from 0%.

The Fern and Mossery said...

very cool and the cuttings look so healthy! I'll have to try it.

Peter said...

We use some vermiculite but mostly just for seed starting.

We never use perlite because it's from a very energy-intensive manufacturing process. We prefer to improve drainage with red lava, which is mined locally (roughly speaking) in Northern California.

But then we also don't use peat for various environmental reasons. That's what happens when you're in Berkeley.

Hà Xuân said...

I've been reading your blog for sometime now (I discovered it when I was searching for "Amaryllis"). I think I'd better say "Hi".
I'm from Vietnam. I've been using vermiculite ever since I'm into African violets. I mix the stuff with other things to pot my AVs in.
Thanks for the new use, Mr S.
(Oh, I have a blog, too, should you be interested. Check it out here

Ivynettle said...

No offense meant :) It just seemed very little to me, but then I suppose you might also not have the facilities we have (and, truth be told, there are people at my workplace - journeymen even - who manage to get similar results with geraniums, make of that what you will)

Ivynettle said...

Yep, me again :)
Just wanted to say, I was really just surprised - not sure I got that across.
(Though I have to admit, I do have a tendency to be unpleasantly smug since managing to have 100% success with Lantana camara, which we haven't managed in the recent years.)

mr_subjunctive said...


No offense taken, either.

Now Lantana -- Lantana we can do. Granted, we've only tried a small batch so far, maybe ten cuttings, but at least all ten rooted.


How is perlite energy-intensive but vermiculite isn't? Aren't they basically the same process?

I try not to use peat any more than I have to too, though that's because I don't like it, not because I'm concerned about the environment. Not that I'm not concerned about the environment.

I use some perlite, though not very much anymore: someone at Garden Web turned me on to using fired clay particles (we have one that we sell as an "aquatic soil") as a soil additive. It's heavier, but it does improve drainage a lot. I'll have to post about it sometime.

Plant & Gardening Tips said...

Thanks for the tips. I can't wait to try this on my grandmother's house.

Peter said...

We don't use perlite because we have a suitable alternative - lava - that does not require high energy to create.

We use very little vermiculite for the same reasons, but there are not good alternatives for the little we do use. But we keep it to a minimum.

Another alternative to perlite is pumice, lighter than lava, less energy than perlite.

Anonymous said...

When you say vermiculite can be used to grow plantlets from leaf cuttings of certain plants, what are you mixing vermiculite with? And what percentage of the planting medium is vermiculite?

mr_subjunctive said...

1) More vermiculite,


2) 100%.

Anonymous said...

LOL!...ok thanks! I thought that's what the case was but wasn't sure verm could be used alone for any purpose.

sheila said...

I stopped using vermiculite a while back because of concerns about the dust being bad for your lungs - does anyone have any current info about that? And is perlite dust equally dangerous?

mr_subjunctive said...

Last I knew, they were both bad. I think I read something a while ago saying that Massachusetts had set up guidelines for length of exposure to the dust, or what they considered a maximum safe level of dust in air, or something like that. I don't remember getting any specifics on what that level was, or which of the two was worse.

Anonymous said...

Great blog - thank you for all the useful info!

Do you use a rooting medium when you are taking the cuttings?

mr_subjunctive said...

I don't understand the question. We cut a piece of the plant off, stuck the lower end in vermiculite, kept the vermiculite moist, and when roots had formed, we potted it in soil.

Anonymous said...

Shows what I know - I have always used salicylic acid when taking cuttings - I seem to get close to 100% success - but didn't realize that it wasn't necessary.

Thank you for the eye-opener - off I go to purchase vermiculite!

boddah said...

oddly enough i have had a very easy time with shefflera... i am completely inexperienced in cutting plants and am not sure i have ever produced a cutting from another plant.

i just stick them in water to my hands liking, and give a "trunk" with multiple "stems" ample time to get comfortable and shoot out roots. if the water gets ratty i dump it and give it new water to my hands liking. i also take the plant out of the water as often as i can and gently blow (warm air) onto the roots. you need to switch the water to provide oxygen, and your body provides carbon dioxide to the plant.