Purple Plum Air Layer

[ColinFraser]

I'm building a new shed/garage/workshop at the back of my yard, and a low branch on my purple ornamental plum tree (Krauter Vesuvius I believe) was leaning out into the walkway to the new door. I know these trees aren't considered ideal for bonsai, but since the branch had to go anyway, and I don't have much experience, I wanted to give air layering it a try.

 

[ColinFraser]

I ring-barked it in late February, applied a wire tourniquet below the upper edge of the cut, wrapped the site in sphagnum, and then surrounded it with a small pot full of turface.

 

[ColinFraser]

Now it's 2 months later, and the branch really has to go, ready or not!
Yesterday I unwired the pot and let the turface spill away. I was relieved to see some roots! Probably not enough to guarantee survival, but enough for me to call this foray a success.

Unfortunately, roots are only growing from one side of the cut:


On the backside you can see nice swelling, good callus, and also the trees attempt at healing the cut, but no roots. As you can see, the branch is at a steep angle, and this may have played a part. The roots all emerged on the downward facing side, which may have stayed wetter whenever I watered the attached pot.

 

[ColinFraser]

I cut it off anyway, since I'm tired of ducking every time I enter my construction project!


The branches had since completely leafed out, and there were several six-footers feeding this. I chopped it downto reduce water loss and potted it deep to keep it from falling over.


So, right around two months from ring-bark to separation. Had I given it three, that pot would probably have been full of roots. That's definitely the plan with the Japanese maple layer I started about a week later! I'll update this thread with the survival verdict when I know.

 

[Plantermunn]

I have not tried an air layer yet. I have my eye on a peach tree.

I hope it makes it for you.

 

[ColinFraser]

I have not tried an air layer yet. I have my eye on a peach tree.

I hope it makes it for you.

Thanks. Even if it doesn't make it, at least it kept me from fussing with the Japanese Maple layer that I really do care about!

 

[daygan]

@ColinFraser , thanks for this documentation. I have a tree of the same variety that I was given permission to dig from someone's yard on which I may be doing a ground layer eventually. It's good to see that they do root well. Also, I don't know about them not making good bonsai - Maria and Andrija in Croatia have some really nice Prunus cerasifera of the generic green leaf variety (i.e. their Prunus cerasifera #5). In my opinion, with good development, these could make really nice bonsai.

 

[ColinFraser]

I don't know about them not making good bonsai -

I was careful to say that they "aren't considered ideal for bonsai." I think one of the big limiting factors is their frequently short lifespan; it's often cited as 10-20 years in the landscape. Even if it took to pot culture well and the leaves reduced nicely (not assumptions I know enough to make), it might not live past the stage where it just started to look good! I have also heard of some living much longer.

The plant itself is beautiful though, and the spring flower show alone is worth giving it a try . . .

 

[daygan]

ah, I see what you mean. Although, I have heard it said that the lifespan information that most sources are pulling from is actually data that was developed years ago for the forestry industry, and that the numbers are actually a reference to the amount of time that a particular species typically has wood that is viable for use as timber, not an exact study of the number of years that the species might actually stay alive. I'm sure (hope) that in potted culture they could easily live beyond the 10 - 20 year estimate - after all, we are frequently doing things that renew/regenerate the life-supporting systems of the tree.

... and you're right - regardless of all that, the beauty of the spring flowers makes it worth trying!

 

[GrimLore]

We "had" a beautiful one a few years back that we cutback and trimming first season leaving it in the nursery pot. Second season it looked great and was potted in a 8 x 10 inch pot. Ramification went great for two more seasons and for no good reason it just dropped all foliage and died Local Botanists here tell me that they live 12 - 16 years max in our climate... Had I known that in the first place it would have saved me a LOT of jumping through hoops trying to save it. It "was" a very nice tree though and I can see a frown on my Wife's face when she sees that pot Just giving you a heads up and hope you have better luck!

Grimmy

 

[ColinFraser]

So I did a little more searching, and CalPoly lists my particular cultivar as having a lifespan of 40-150 years. That's more like it! http://selectree.calpoly.edu/treedetail.lasso?rid=1158

This is still just an experiment, but I'll certainly continue to grow the thing as long as it wants to stay alive. There are probably other branches I could air layer to get a better start on a bonsai if I really was invested in training his species . . . This branch was coming off anyway, but the others hide an ugly view of a utility pole, so they stay put for now!

 

[Bunjeh]

So, right around two months from ring-bark to separation. Had I given it three, that pot would probably have been full of roots. That's definitely the plan with the Japanese maple layer I started about a week later! I'll update this thread with the survival verdict when I know.

Thanks for this. This is probably the most concise lesson on airlayering I have found. Bravo.

 

[ColinFraser]

One fun thing about these purple varieties is that they are so full of anthocyanin (the purple pigment) that virtually every part of them is colored. You can see the bright root tips in some of the above photos. Perhaps more interesting is the wood - a clean chop reveals a disconcertingly purple cross-section! Even the callus has a tint to it.

 

[GrimLore]

So I did a little more searching, and CalPoly lists my particular cultivar as having a lifespan of 40-150 years.

Thank you for that information! I will look for one here and perhaps surprise the Wife with it. The Thundercloud we had it rated at 20 years max but rarely sees that in 6b as well as several other varieties.

Grimmy

 

[ColinFraser]

Thank you for that information! I will look for one here and perhaps surprise the Wife with it. The Thundercloud we had it rated at 20 years max but rarely sees that in 6b as well as several other varieties.

Grimmy

If I start any more, I'll let you know

 

[Brian Van Fleet]

You separated it awfully fast. I hope it works, but I typically wait until I see a lot more roots, and some hardening off of roots.

 

[ColinFraser]

You separated it awfully fast. I hope it works, but I typically wait until I see a lot more roots, and some hardening off of roots.

Yes; I had to take the branch off to move 4x8 sheets of osb and 14' 2x6s. I was originally going to just lop it off, but I had just enough time for this experiment. Like I said, my primary aim was practice at the technique, and I got that. If the thing survives, great; if not, no harm. It definitely emboldened me to start the layer on a family Japanese Maple that I had been hesitant about : http://www.bonsainut.com/index.php?threads/japanese-maple-air-layer.18273/
That one I will definitely let go for longer.

 

[JoeR]

I only got to airlayer a plum and a blueberry this year because of timing issues however I checked them a few days ago and they both have roots so far. My plums roots seem to be mostly on one side too and not sure why. I suspect it may be the side that gets more Sun thus warmer.

 

[daygan]

the side that gets more Sun thus warmer.

... or it could be: more sun, and thus more leaf growth, and thus more auxin production, which travels downward and stimulates more root growth in the areas where it collects in the cambium at the bottom of the air layer.

 

[JoeR]

... or it could be: more sun, and thus more leaf growth, and thus more auxin production, which travels downward and stimulates more root growth in the areas where it collects in the cambium at the bottom of the air layer.

Kind of what I was saying, just better growing conditions and so more auxin. Planned on rotating the tree to balance it out (it's in a nursery container).