Defoliation 101

[markyscott]

that ficus in the 4th picture is going to do much better through winter after full defoliation.

It’s true that there are a lot of people who believe in removing every leaf on their trees without thought to strength balancing, strengthening interior shoots or redirecting growth and I won’t try to change your mind. I‘ve done that in the past too. For me, my trees reliably survived this approach and produced new growth, but year-on-year, they weren’t getting any better. So I adjusted my techniques and I’m much happier now with their pace of development. If, after a few years of work, you are not happy with how your trees are progressing, perhaps think back on this thread and you might find in it an alternate approach that will work better for you.

S

 

[choppychoppy]

Sorta got em posted.....

 

[ABCarve]

Do you have any advice/info on defoliating broadleaf evergreens. Which ones tolerate/respond to it? Is there a rule of thumb?

 

[defra]

I think the tree will be fine, but I don’t think you advanced it’s development by completely defoliating. I’d look to your indoor setup to try and figure out why your trees drop leaves when they’re moved outdoors.

Scott

my indoor setup is an old aquarium with lid on the Windows sil in front of a big south facing Window no extra artificial lights tough its growing all winter but not as good as outside its in there because of the dry air wich i cant avoid otherwise.
at least it improved by wireing with a clear view on the branch structure.
ill have to compare the improvement after this outdoor season with the preveous years to find out of you are right ill let you know by then

 

[markyscott]

Sorta got em posted.....

View attachment 304606View attachment 304607

Hi CC. Thanks for taking the time to post your pictures. Sorry to ask because of the technical problems you’re having, but can you point out which picture demonstrates that lateral buds are activated by defoliation alone without shoot pruning? It’s not clear (at least to me).

My experience is like this.


These extending shoots were defoliated and wired out, leaving a couple of leaves around the terminal buds. I did not shoot prune it as I wanted it to extend and thicken. The shoot originally ended about the same place the wire does. As you can see, no lateral buds were activated as a result of the defoliation. The shoot just continued to throw growth from the terminal bud.

S

 

[markyscott]

my indoor setup is an old aquarium with lid on the Windows sil in front of a big south facing Window no extra artificial lights tough its growing all winter but not as good as outside its in there because of the dry air wich i cant avoid otherwise.
at least it improved by wireing with a clear view on the branch structure.
ill have to compare the improvement after this outdoor season with the preveous years to find out of you are right ill let you know by then

Great! I suspect it’s the low light levels with your winter setup, but I look forward to hearing about your experience.

While you’re waiting, here’s a thread for you to read documenting the difference adopting these techniques made in the development of one of my trees.

Developing a large Willow Leaf Ficus

... and lessons learned. This was a tree I purchased in about 2008. Being a slow learner, I wasted a lot of years of work on the tree. I defoliated it a couple of times a summer and wondered why my growth was so poor and development was so slow. Starting in 2013, I completely changed my...

www.bonsainut.com

Scott

 

[just.wing.it]

Thanks @markyscott !
Nice breakdown.

 

[markyscott]

Here are a couple of additional good sources of information describing the techniques associated with defoliation as I subscribe to it.

The Trident Maple

As I was preparing for my apprenticeship in Japan, there was some big decisions to be made. I had about 15 or so Bonsai trees and nowhere to keep them during my absence. I had to make the tough d…

peterteabonsai.wordpress.com

#2 Trident Maple Project (con’t)

#2 Trident Maple Project (cont) Trident Maple Project #2 (July 2012) As promised, here is an update of my other Trident Maple project. The last post I wrote about this tree was in June of 2012. P…

peterteabonsai.wordpress.com

Scott

 

[markyscott]

Do you have any advice/info on defoliating broadleaf evergreens. Which ones tolerate/respond to it? Is there a rule of thumb?

My experience with broadleaf evergreens is pretty much restricted to oaks, olives and tropicals. Was there one in particular you were interested in? If it’s not one of those, I can try and find out.

- Scott

 

[choppychoppy]

Hi CC. Thanks for taking the time to post your pictures. Sorry to ask because of the technical problems you’re having, but can you point out which picture demonstrates that lateral buds are activated by defoliation alone without shoot pruning? It’s not clear (at least to me).

My experience is like this.
View attachment 304617

These extending shoots were defoliated and wired out, leaving a couple of leaves around the terminal buds. I did not shoot prune it as I wanted it to extend and thicken. The shoot originally ended about the same place the wire does. As you can see, no lateral buds were activated as a result of the defoliation. The shoot just continued to throw growth from the terminal bud.

S

Yeah sorry these pics blow. I'll go get some better shots and try to update a proper post.

So in the large trident defoliated...
Over on the left you can sorta see a low shoot with leaves on the end. Blurred and tiny I know....sry. So that was defoliated but the tip growth was left uncut and it did regrow the new leaves without much new extension. The regrown leaves on the shoot is shown here. So it does seem to reflush even without cutting the tips too.



But for sure on a crepe myrtle I've never seen any latent growth/ramification from leaf removal. Only cut points. That's the first pic of the triple. Pretty much exactly what you referred to.

I'll look to see about what tropical pics I can drum up. I know with most ficus when leaving the growing tip while defoliating you will definitely get deeper budding. But this may be more of tropicals strictly reacting to the renewed sunlight on the interior and not any genetic reasons.

 

[choppychoppy]

Here are a couple of additional good sources of information describing the techniques associated with defoliation as I subscribe to it.

The Trident Maple

As I was preparing for my apprenticeship in Japan, there was some big decisions to be made. I had about 15 or so Bonsai trees and nowhere to keep them during my absence. I had to make the tough d…

peterteabonsai.wordpress.com

#2 Trident Maple Project (con’t)

#2 Trident Maple Project (cont) Trident Maple Project #2 (July 2012) As promised, here is an update of my other Trident Maple project. The last post I wrote about this tree was in June of 2012. P…

peterteabonsai.wordpress.com

Scott

Yep. I've been enrolled in both tracks of his intensives so I'm pretty much doing his plan on most everything these days

 

[Warpig]

My experience with broadleaf evergreens is pretty much restricted to oaks, olives and tropicals. Was there one in particular you were interested in? If it’s not one of those, I can try and find out.

- Scott

If I may piggyback off of this question, I was wondering about boxwoods. Would you approach it the same as say you would a maple? I guessing you brought up broadleafs since their canopys tend to be fuller?

 

[choppychoppy]

I am also about to so defoliation #2 on this tree so I will take some new shots as well and post the results. I can do a ficus or two as well

 

[markyscott]

Yeah sorry these pics blow. I'll go get some better shots and try to update a proper post.

So in the large trident defoliated...
Over on the left you can sorta see a low shoot with leaves on the end. Blurred and tiny I know....sry. So that was defoliated but the tip growth was left uncut and it did regrow the new leaves without much new extension. The regrown leaves on the shoot is shown here. So it does seem to reflush even without cutting the tips too.

View attachment 304638

But for sure on a crepe myrtle I've never seen any latent growth/ramification from leaf removal. Only cut points. That's the first pic of the triple. Pretty much exactly what you referred to.

I'll look to see about what tropical pics I can drum up. I know with most ficus when leaving the growing tip while defoliating you will definitely get deeper budding. But this may be more of tropicals strictly reacting to the renewed sunlight on the interior and not any genetic reasons.

LOL - I must be dumb as a rock. What shoot was defoliated? The spring shoot you appear to be photographing still appears to have all it’s leaves on it.

Scott

 

[markyscott]

If I may piggyback off of this question, I was wondering about boxwoods. Would you approach it the same as say you would a maple? I guessing you brought up broadleafs since their canopys tend to be fuller?

Forgot about boxwoods - yes I work with them as well and treat them more or less the same except I never remove all the leaves on any branch. In development, I build branches by letting the shoots extend. To let light and air into the interior, I remove the old leaves, leaving the the new leaves at the growing tips alone. For trees in refinement, I let the spring shoots extend. Then I cut back to the first pair of new leaves and remove last years leaves.

- Scott

 

[markyscott]

Yep. I've been enrolled in both tracks of his intensives so I'm pretty much doing his plan on most everything these days

We are truly at a rare place in our country in that there are a number of talented artists now all over the country. Bjorn is one of them. I’ve worked with him several times and I’ve really liked him. He’s patient and knowledgeable. I’ve brought him down to Houston a couple of times, but the last planned trip ended up being a Hurricane Harvey cancellation.

Scott

 

[choppychoppy]

Ye

LOL - I must be dumb as a rock. What shoot was defoliated? The spring shoot you appear to be photographing still appears to have all it’s leaves on it.

Scott

Yeah this has already been defoliated completely once on April 18th. All leaves are regrown. That's the second flush of growth on that shoot not the first spring growth. The before and after defoliation pic is this year a month ago and now.

 

[misfit11]

Great thread, Mark. Thanks for sharing your knowledge. I've just began a regimen of partial defoliation on my D-trees this year. This thread is perfect timing!

 

[ABCarve]

My experience with broadleaf evergreens is pretty much restricted to oaks, olives and tropicals. Was there one in particular you were interested in? If it’s not one of those, I can try and find out.

- Scott

Laurus noblis I have one and have always wondered. I have cut old leaves in half which didn’t seem to do much. Maybe a timing thing?

 

[Daniel_UK]

What a great read - thank you @markyscott . It also makes sense as my understanding is that the hormone auxin determines the growth of dorman laterals. If you shoot prune then auxin is no longer sent down the stem and therefore lateral growth is no longer inhibited and therefore lateral buds grow. By leaf thinning, auxin is still following down and inhibiting lateral growth.