Rooting avocado cuttings

It is very rare to get scionwood (i.e., dormant buds, leaves removed) to successfully root, in fact I’d say I’ve only succeeded once previously in 30+ attempts. But, this “Wilma” cutting that sat green and ungrowing since late April sure seems to be indicating that it succeeded in producing roots with this new flush:

But I won’t say it’s a certain certain success yet, I’ve seen some top growth without roots within the first few months. If this growth doesn’t wilt within a month or so then I’ll call it a success, though.

It has still been under this jar, so the real test will come when that is removed:

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Test failed! It wilted as soon as the jar was removed, and when I checked the dead twig for roots, there were none.

The in-ground Aravaipa clone has been growing nicely since that last update a few posts up, but it’s still a fraction of the size it would be if I’d grafted it at the same time I started rooting it:

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A couple other updates worth mentioning… this Long South Gate cutting just recently dropped its leaves from last season while pushing a new flush, so I’m hoping this is a sign of roots (it’s been without a humidity dome for 2+ months now):

I also have recently cloned our largest seedling in the project so far, this 8 foot Mexicola Grande seedling that went in the ground this March:

It’s not surprising, as the cutting was taken from just above ground on a water sprout over the winter, you can see where it was removed here:

These show the clone currently (on top) compared to what it looked like a few months ago:

It’s interesting that the leaves became chlorotic while waiting for roots to form, but then greened back up again over the summer. I didn’t even realize that was possible!

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[quote=“swincher, post:19, topic:34254, full:true”]

“Unfortunately, most of the YouTube and TikTok videos about rooting various things are fake and just made for the clicks. There are also legit ones, but it can be hard to be sure which is which.”

I agree. Rooting tree is very difficult thing to do. I tried 12 of avocado cuttings, and nothing rooted. I used Aloe Vera and onion method as some of Youtuber used. Nothing worked. If what youtuber showed was true, it has to be Philipine or some very wet and humid country. I can see the ground in the video, which was so wet.

What cultivars? What type of cuttings (fresh growth, mature growth, with or without leaves)?

I have never heard of that, but would not expect it to work. I’ve tried both with rooting hormone (clonex gel) and without, and saw similar results both ways. It may help more for some cultivars than others, though. I would not recommend dipping them in any other things, like aloe or onions (?!?).

It was Fuerte. I had left a few leaves (leaves were cut in a half). Did your clonex method work? How many cuttings were successful out of how many if it was successful? What cultivar?

I’ve done it both with clonex and with no hormone, they seem to have about the same success rates either way, which is to say not very high rate of success.

The list linked above is updated somewhat regularly, though I’ve got at least a handful of new ones I haven’t added yet, here’s where I linked that:

Most of my successful clones are from cuttings I took from seedlings I had grown myself, most of which are seedlings of fully Mexican avocado cultivars.

Fuerte and other Mexican/Guatemalan hybrids (e.g., Bacon, Hass, etc) seem to have very low success rates based on the old journal articles at the top this thread, though I’ve also rarely tried anything other than pure Mexican cultivars since that’s all I’m including in the PNW avocado project. I did have some success with seedlings of Bacon and Zutano, but I haven’t tried to clone those actual cultivars, just their seedlings.

In terms of success rates, I mostly do them in small batches of 2-3 at a time, and usually around half of them wilt within the first couple weeks. Nearly half of the remainder end up wilting a few months later when I remove the humidity domes. My best guess at overall success percentage is ~30% following this method described above, but it’s somewhere around 60% if you only count the ones that don’t wilt right away (in the water stage):

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Very impressive to see so many different varieties. Why do you use cuttings from seedlings? Don’t you want to use mature good fruit cultivar so you can have the same gene in the cuttings? if you use seedlings, they may not have the same trait its mother trees have.

I’m organizing a cold-hardy avocado breeding project in the PNW, where we hope to eventually test many thousands of seedlings of hardy cultivars in an area that’s usually considered to be too cold for avocados to grow. Whenever I graft a known cultivar onto a seedling, I attempt to root the top part that is removed from the rootstock. This way, those seedlings get to be evaluated twice, perhaps by different project members in different microclimates.

Fruit quality is not something we will be selecting for initially, just hardiness. If 10+ years from now we have successfully selected enough hardy cultivars to justify selecting for fruit quality, that will be the next stage.

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Hey swincher
I know we talked about this but I’m getting ready to try some rootstock cloning and I think it’s better than trying to root cuttings, which I have done once and everything failed after many months. So if most fail, you’re wasting a lot of cuttings. With a nurse seedling, if you fail at rooting the top part, you still end up with a grafted tree.
In this method, you can make multiple clonal trees from one nurse seedling.

Real world example - I get Bacon avocados from a friend and his trees were planted in 1980 so they’re 40 feet tall. I can pick up rotten bacons from the ground that the squirrels chewed off and the seeds inside are still good. (I have about 40 seedlings at the moment with 30 more seeds being germinated). I recently got a large Duke tree from another friend that is about to die so I cut off a bunch of wood from it. I grafted a whorl from the Duke to a Bacon seedling. If it takes there could be 5 sprouts from it. Once it takes and starts to bud you put it into a closet for 2 weeks and the buds stretch out very long and white. Then you score the white stems and put rooting hormone on them and an air layering pod. Best case scenario I get like 5 own root Duke trees which are worth a lot. Worst case I end up with a weird shaped Duke tree on Bacon which is no problem because I can try again by burying the graft union and trying to get roots above the graft. Trying to root cuttings seems more straightforward but you usually end up with nothing from your efforts

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Yes, that’s true if your primary goal is having some particular cultivar on its own roots, or having a large number of clones of a few cultivars, and you have access to lots of seeds that you don’t want to also grow in their own right.

For our project, we’re evaluating virtually every seedling in the collection in its own right, and until we find any cultivars that do well here, there’s no reason to have a large number of clones of any particular cultivar.

I mostly root cuttings that would otherwise be thrown in the compost, including the tops that are cut off seedlings being grafted and the tips of branches removed from multi-graft trees when they are pruned to keep their different varieties in balance.

Since the cuttings for rooting are of a different part of the branches (tender growing tips) than the cuttings that are best for grafting (mature wood with buds visible at leaf nodes, and bud whorls) these two propagation methods are not in conflict, and can even be complementary.

I’ve had success rates as high as 80% rooting the tops removed from young seedlings, which basically ensures many of those seedlings can be tested both as a rootstock and in their own right. That practice alone has helped me boost the number of trees to keep up with demand from members.

In a decade or so, if we have a good list of new cultivars from this project, it may make sense to use a propagation method more like what you describe for the best few varieties that can survive. Until then, diversity is my goal, not clonal propagation on a large scale.

I’m attempting to get Mexicola on its own roots for the first time this year. I took two cuttings pretty close to the stage recommended by the paper I quoted up above in this thread:

Here are what I just cut:


My aquarium has been retired with the death of its occupant, so I’m using my backup method of callusing the cuttings before they go in soil. They go in bottles of regularly changed water, under a dome, atop the microwave light bulb, with the door cracked open to keep it on. It’s getting a little cramped under the dome because it already had the latest Duke cuttings that were taken a few days ago:

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These cuttings of the cultivar “Linh,” a backyard tree identified & shared with me by @JohannsGarden, are just now beginning their first new flush, even though I took the cuttings last winter:


They have both kept such nice green leaves when rooting, most other avocados turn all chlorotic while waiting to root. With 100% success rate so far (2 of 2), I’ll be rooting some more of these this winter. Very excited to get to try this one on its own roots outdoors in a year+. Hopefully the greenhouse graft sets some fruit next year, I’d love to try it.

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One of those Linh clones is really starting to grow!

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I planted out my first couple avocado trees this week, including one of the “Linh” clones (Tree #308). Here was me making sure the hole was deep enough:

It had nice enough looking roots, but it shows what I have seen in 100% of avocado rooting, that the roots only come from the very end of the stem, no matter how much stem you bury:

I decided to expose more of the stem when planting out, to bring the root crown closer to the surface:

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Unbeliveable how red the first flush is of this variety. Beautiful!

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Yes! It also has some of the sweetest smelling leaves of any variety I’ve grafted. Even if the small fruit are only mediocre (I haven’t actually tried them yet, but do have flowers expanding in the greenhouse this year), “Linh” deserves to be grown even just for its leaves.

Here’s another photo from last year that I assume I posted before:

I do also have an update on the Linh clone that I planted out a few days ago. This morning our low was 28.0°F (-2.2°C), and I was not surprised to see that tender new flush turn crispy. I probably should’ve waited another week to plant it out! The hardened leaves took it fine, though:

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oh, thats sad. They didn’t last very long. I can feel with you. I know this feeling very well and have experienced it many times, that after winter you have plans what you are going to plant out as soon as it gets warmer. Then a few warm and sunny days and you can’t hold back any more and you’re gonna do what you shouldn’t do yet and put your plants in the cold ground, which is most of the time a shock for them, or you forgot to cover it in a late frost that was not expected. :face_with_raised_eyebrow:

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In this case, I did know the freeze was coming, but decided to see how it would take it instead of covering it, since I’ve never cold-tested this variety. I’m sure it’ll bounce back fine soon enough. I think tonight will likely be our last frost.

We are going to have -2/-3 on friday morning. Afterwards it may get slowly warmer here as well. But becouse of our high altitude of over 500m/1500feet, we sometimes can have light frosts up to May.

Is linh a true variety or is it only a given name by a friend?

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