Is A Horse Chestnut A Good Tree For Bonsai?

The Horse Chestnut tree, also known as the Conker tree is not a good tree for bonsai. Although it is easily found for free and grows quickly, it just has all the wrong characteristics.

I do own one that I grew from seed and I do not regret it. (You can see how it’s developing in my Horse Chestnut Bonsai Progression).

They are a lot of fun and very easy to grow. They are also very easy to care for, but everything about them just goes against what you want from a species for bonsai.

They are good to play around with, but you really can’t expect much from them. If you find one in your garden, sure play around with it, but I would not go out of your way to get one. They are an iconic tree, but they are not an iconic bonsai.

Is A Horse Chestnuts Foliage Good For Bonsai?

For me their biggest issue is their foliage. I love the leaves, but they are a nightmare for bonsai.

Leaf Size

Horse Chestnut leaves are made up of what almost looks like 5 leaves in one. They are like a hand shape with its big fingers spread out wide, which is exactly why I hate them. As beautiful as the leaves are, they are huge.

When growing them as bonsai you can get the leaf size down in size compared to a full size tree, but even this “smaller” version is still pretty big.  

The leaves also have a huge petiole (the little stem bit that connects the leaf to the tree). Honestly it they must be a couple of inches long, they just look ridiculous and are all part of why these trees are not ideal for bonsai. 

Internode Length

Another downfall of the Horse chestnut is its internode length. The growth is quick and strong so the internodes can be huge. You can easily find a couple of straight inches between buds and leaves. This is really not ideal when you trying to keep a tree small and have tight ramification. 

I have found it is hard to build a good structure as everything is so stretched out and it’s just not designed to be a small tree with tight foliage. 

Of course the way round this is to have a slightly larger tree but this still isn’t ideal. This thick course growth also means you will never see a mame horse chestnut. It’s just never going to happen.

Is A Horse Chestnuts Growth Rate Good For Bonsai?

Horse Chestnut grows fast and its grows strong. I imagine to support its huge leaves.

Response To Pruning

I’ve always found that Horse Chestnut responds well to pruning. It will always send out new buds wherever you prune. The problem is that the new growth is strong and you get a big straight internode before the new leaf.

Back Budding

Horse chestnut will back bud. if you look at a branch in early spring you will see buds all down the tree. You will often see the big main bud at the end of the branch and then two, maybe even 4 buds almost directly below this.

You will also find these types of back buds growing at the collars of branches. I normally just rub these buds off to stop them in your track, but if you do not, you will have to come back later and prune them back. 

Ramification

Trying to build very thin ramification is difficult. The shoots will divide, it just that the growth is too course. This is why you need to make you bonsai a large tree.

I feel like it is impossible to get the ramification really tight and compact on these trees. You are always going to have long internodes and spread out leaves.

Is A Horse Chestnuts Styling Ability Good For Bonsai?

As I have already touched on, you will need the tree to be quite large so that the thicker growth and larger leaves will be in proportion. Apart from this you can easily style them like any other deciduous tree.

Wiring

You can wire Horse chestnuts, but you will need to do this while the shoots are young as they can thicken up quickly and become hard to bend. You will also find it is very hard to avoid straight sections due to the large internode length and fast growth. 

You can try and put movement into these areas, but you have will to do this when the shoots are very young, which is difficult as they are often still very fragile and can easily break when you are applying the wire..

Is A Horse Chestnuts Fall Colours Good For Bonsai?

The leaves can be okay during autumn. They will turn a bright yellow and they usually look better from further away.

When you look at the tree as a whole it can look pretty nice, when you get a big closer the leaves can be a big ugly but they are not the worst leaves. I have found they will also drop very fast which means you do not really get long to appreciate them.

Is A Horse Chestnuts Winter Silhouette Good For Bonsai?

The winter silhouette can be okay but you are really going to notice all those little thick straight sections caused by the large internode length.

Horse Chestnuts also have huge buds that set in the autumn. They are big and brown and sticky looking. They are pretty strange and they certainly stand out among the trees on the bench. You might panic and think your tree is about to leaf out, but it’s okay, it won’t do anything until spring. 

Is A Horse Chestnuts Bark Good For Bonsai?

The bark on Horse chestnuts is pretty good. My tree is still relatively young but it already has some nice character and looks a lot older than it is. It will quite quickly get that woody look to it.  

As for wound healing, honestly, I’ve not really dealt too much with this. Most of my wounds have been from pruning and I have always left a little nub where I have pruned. This has then just died back, but I will have to do more experiments on this.

Deadwood Opporunities

Horse chestnut is not the type of tree that suits deadwood. However, if you have a thick enough trunk some carving might suit it quite well. This is generally  good advice for all deciduous trees.

Is A Horse Chestnuts Roots Good For Bonsai?

Horse Chestnuts roots are actually pretty cool. They have a the most beautiful red colour to them, but apart from that they are just like any other deciduous tree. This means if you time it right you can really trim them quite a lot.

I have found that they grow equally as fast as the top of the tree so you will have to prune them regularly so it’s a good thing that they can handle the work.  

Is A Horse Chestnut Easy To Care For As Bonsai?

Caring for a Horse Chestnut is easy; they grow fast and they don’t need much effort which is why trying to tame them for bonsai is so difficult. 

You can read my Care Guide for Horse Chestnut .

Conclusion

Horse Chestnuts are beautiful trees although they are better suited for the park than the bonsai bench. They grow too fast and coarsely and their large leaves don’t help matters. They are just very difficult to keep small and look convincing as bonsai.

I wouldn’t go out of your way to get one, but if you find one in your garden, go for it. You will have a lot of fun, but you need to understand that you will not really get anywhere with them as a bonsai.