Zelkova defoliation


#1

I have a mature Zelkova purchased towards the end of last year that did well over the winter and has a full set of healthy leaves. The leaves are quite large though and I am hoping to defoliate this year. It makes me a little nervous completely removing all the leaves since I have never defoliated a tree before. It would be a shame for it to die from doing something too aggressive. Are there any specific tips or tricks? Any reason not to completely defoliate other than the tree being unhealthy (which it is not)?

I have read the best time to perform defoliation is in the middle of summer (mid-June) when the new branches have hardened. It looks like you also cut the leaves through the leafstalk. Any additional suggestions? The tree was repotted ~ 16 months ago.

This link was helpful: https://www.bonsaiempire.com/basics/styling/advanced/defoliation

Thanks


(Jonas Dupuich) #2

Zelkovas, like maples and elms, are good candidates for defoliating. What’s your main goal for defoliating? (uploading a photo could be helpful)

Defoliation can be used to:

  • reduce leaf size
  • balance vigor
  • improve ramification (see related post for details about what this means)

Defoliation can also be partial. If the tree is young and better ramification is the goal, you can completely defoliate the tree. If the tree is more developed, removing the large leaves and leaves near the outside of the silhouette but leaving smaller, interior leaves will strengthen the interior areas.

It’s very stressful for the tree, but if your tree is healthy and you’ve been feeding this spring, you’ll have prepared it well.

After defoliating, leave the tree in the sun and mist or overhead water regularly. Don’t over-water as the tree won’t need as much water until the new leaves appear.


Defoliation for ramification?
#3

Thank you for the response, Jonas.

My main goals are to reduce leaf size and improve ramification. The ramification is pretty good though, so my primary goal is to reduce leaf size. It sounds like the better option in this case would be to remove the large leaves and let the smaller ones remain. It would also make me feel a little more comfortable leaving some leaves on the tree. I have not been fertilizing this summer, so I will have to make sure to do that before I go ahead and remove leaves.

I have included a couple of pictures. Unfortunately I do not currently have photos from the winter to adequately show the branch structure.

Any other suggestions after seeing the photos?


(Jonas Dupuich) #4

Thanks for sharing the photos! It looks like now would be a good time to do some cutback too. Cutting back to 2-3 leaves all over the tree will reduce the bulk of the foliage and then you can defoliate the strong areas after that.

In general the tree looks really healthy. Do note that interior leaves currently used to shade will be in the sun after cutback and defoliation. They can burn easily if the tree is placed directly in full sun after defoliation.


#5

I performed a cutback with no defoliation. The leaves were relatively small on the interior and at the bases of the branches, so it seemed as though defoliation wasn’t necessary. Would appreciate hearing people’s thoughts though. Here are some before and after photos!

Before:

Cut leaves:

After:


(Jonas Dupuich) #6

It looks like the general density is pretty even - good job with that! As a lot of the leaves are still pretty large and the canopy full, I’d likely remove up to half of the remaining leaves.

I just worked on a few zelkova last week, pulling more or fewer leaves on different trees to see how each come out.


#7

Nice! Do you have any photos from the work you did? I would love to see your experiment and how it turns out.


(Jonas Dupuich) #8

I did get a couple of photos but they don’t reveal much as the trees I defoliated were all back in leaf in no time with no significant difference between them.


(jamie swords) #9

I defoliated my zelkova last week


(jamie swords) #10

This is it after 9 days


(Jonas Dupuich) #11

Interesting that the exterior leaves came back before the interior ones. On mine, they all came out at the same time.

I don’t know that that’s anything to worry about - mostly it’s a guide for what will happen the next time you defoliate.