Rooting Cuttings By Etiolation

General Fruit Growing
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Has anyone tried etiolation methods of rooting hard-to-root species, such as persimmon, apple, peach? I first came across the basic method while reading through Garner’s The Grafter’s Handbook and was intrigued. Garner describes basically leaning over the stock plant, pinning it to the ground, and burying it. You then repeatedly cover the shoots that emerge from the buried buds (similar to stooling rootstocks) to promote a blanched, leggy growth that is more likely to root. I found this more up-to-date description/method from Cornell: http://www.hort.cornell.edu/uhi/research/articles/IntPlantProp37.pdf

Edit: Thought I should describe the updated method here to prevent confusion. In a nutshell, the new method is to cover a portion of the stock plant with a light blocking material and allow the shoots to grow. Next, you wrap velcro bands with rooting hormone powder applied to the lower portion of new shoots to keep them dark and slowly acclimate the new shoots to full light. Then, you take cuttings of the new shoots at the semi-hardwood stage and dip them in hormone solution, and treat them as you would other cuttings, preferably under mist.

My research thus far has turned up some articles citing earlier work using etiolation to improve rooting of Japanese persimmons. My Japanese history-studying brother is working on getting a copy of the earlier cited work, so I’ll try to summarize the findings when I get that. Anyway, I’m slowly getting ahead of myself and in to a Quixotic endeavor to create own-root American and hybrid persimmon clones, and this sounds like a promising technique.

There are other techniques in the literature that seem to be successful in cloning D virginiana, but they rely on using short, softwood cuttings from root suckers or intensive micropropagation. Genetic variability also seems to be the #1 factor in success (Izhaki et al 2017).

Update: I got a hold of the bulletin describing rooting Japanese persimmons with etiolation. They use the more modern method described above, and had 41% takes on one variety and 9% on another. Not great, but definitely better than 0%. It also lends more weight to the genetic variability factor.

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Sounds like a lot of work. I would try air layering with wire girdling first. Works with peaches.
I don’t see how you could bury a peach? Usually buried limbs root on most things, but maybe not all? The air layering technique takes time, but can work. It might not always work. I myself have never done it on peach. I have air layered figs, honeyberries, some flowering, shrubs/trees like wisteria. I didn’t even girdle any of those. A user here used to root peaches with air layers. Unfortunately the gentleman has passed away.
See

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I agree about being a lot of work, but it sounds manageable, especially the newer method. With the old method, you don’t need to bury a whole mature plant, just lean a shoot over. I envision laying over a 1 year old graft. With the method described by Cornell, you could just bag a branch or portion thereof, then apply the Velcro bands with hormone after the shoots grow. I’m definitely going to try air layering as well, but it doesn’t sound very promising for persimmons. From what I’ve read, the etiolation class of rooting techniques is reserved for the toughest customers because of the work. Mostly, I’m just curious. And like I said, getting ahead of myself: I don’t have any trees yet!

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Nothing wrong with trying it. I like to breed plants too for fun. Or even just grow out seeds.
I always said it was a hobby within a hobby. Keep us updated.
With air layers I would do a wire girdle for 2 weeks, then put the air layer right over the girdle. The idea is to let hormones gather at the girdle before air layering to increase rooting chances.

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I really like the idea of the wire girdle. If I recall correctly, they use that technique in bonsai. I’ve never been able to wrap my head around removing the bark on an air layer. It doesn’t strike me as an improvement on taking a cutting, but it seems to work for people. The wire girdle makes more sense to me, as the shoot has some transition time as the flow gets cut off.

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This sounds like the traditional method for propagating hops. They dig a trough next to the plant, and bury a vine. The shoots grow up out of the buried limb, and it is rooted by the following spring. Probably don’t do it this way anymore.

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There are definitely some similarities, but also a few key differences. The hops method is more like a basic layering, and the “old” etiolation mehod is more like blanching asparagus, where you want to keep the whole shoot in the dark.

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I had some Krymsk stock i took cuttings from (semi hardwood) this past summer…just put them in shade and covered with glass containers…I did some earlier ones that i don’t think were mature enough and didn’t take…the ones that were taken maybe late June–i had a quite a few that started growing roots and survived into the fall and went dormant… I think the key was constant moisture and lots of heat (it was very warm during this time period///90Fs/humid). I’ll be trying more this summer… I also did some Gardenia and they all took…very easy to multiply…now i have too many.

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A neighbor cut down a D Virginia which had been producing for a long time. I got enough material from it to attempt rooting 100+ cuttings. Probably 30 started to take and then I let them dry out and I lost them. I think that if given the right conditions they should root fairly consistently. D

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Dan that’s interesting to hear! Most of the scientific literature I’ve found so far focuses on D. kaki, but the general consensus is that some individuals are much more likely to take than others. Also, it sounds like sometimes when they find a treatment that has high initial rooting success, it ends up with a lower overall survival rate! I think the one technique that had high success across the board was re-culturing in vitro over 70+ iterations (6.5 years!). Sounds like a tough nut to crack, but glad to hear about some real world successes.

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I forgot to add that i used hormone rooting powder on all my cuttings.

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