Is Boxwood  A Good Tree For Bonsai?

Boxwood is a small evergreen shrub that is popular in ornamental gardens and is mainly used as a small boarder hedge or topiary.

There are a number of different verities found all over the world but the two you will see most used in bonsai are the Common Boxwood (Buxus Sempervirens) and Japanese Boxwood (Buxus Microphylla). You will also hear a lot of people talk about Kingsville boxwood. It’s hard to find exact information on this variant, but my understanding is that this is a form of the Japanese Boxwood variety.

These are not the only varieties that are used for bonsai, but in general I feel the species as a whole is underutilized. It is a very slow growing species, so it can be hard to develop it as bonsai.

I have the common boxwood, so most of what I will be talking about here will be based on my experiences with that, but it should be fairly similar to what you would find with the other varieties. (You can see how it is developing in my Boxwood Bonsai Progression)

Is Boxwood A Good Species for Bonsai?

Yes and no. This species has a lot of positives, but it can be slow, almost too slow.

Boxwood is naturally quite small. Left alone it will only reach 1.5m at most which means they are perfectly suited to being small trees and they have the small foliage to match, which are both very desirable in bonsai.

They tend to grow in a multi-stem fashion which is why they make good dense hedging. This type of growth is okay, but if you do not know what you are doing then it can end up looking like it has balls of foliage on the end of long straight growth, which is not a good look for a bonsai. This is why they are maybe underutilized; people do not know how to style them properly to look good.

As I’ve already mentioned, they are slow growing and most of the stock available is small and thin, with multiples trunks. This makes them great for hedging, but trying to find a boxwood with a just one single decent trunk that would be good for bonsai is very hard.

They can grow in the ground for 20 years and still only be as thick as a pencil. They can make really great bonsais, but their inability to thicken is for me, their main weakness and probably why are not as popular as they could be.

Is Boxwoods Foliage Good For Bonsai?

The foliage is perfect for bonsai. The leaves are a small oval shape and have a beautiful dark green, almost glossy colour to them. They are quite small and compact naturally, but with pruning this can be brought down further.

Their internode length can really start to get tight and you can very easily build dense foliage, which should be no surprise since they are used as hedges and topiary.

Is Boxwoods Growth Rate Good For Bonsai?

The growth rate is painfully slow. As I have already mentioned above they can be very difficult to thicken which is why it can be hard to find good examples as bonsai.

The common boxwood is supposedly faster growing than the Japanese variety, although strangely I have seen more Japanese boxwood with better trunk development.

If you can source and old tree that has been growing for many years in the ground, you are going to be off to a much better start than using nursery material. The boxwood I have is from a nursery. It is very thin and now trying to get it to thicken is going to take a few decades, if ever. 

The growth can get straight and long, but if you are pruning often, this will be not be an issue.

Response To Pruning

Boxwood will respond well to pruning. When they do actually start growing, you can trim them back and they will sprout new buds just below where you pruned.

I find I only get to prune mine at the end of spring. It has usually put on enough growth to be trimmed by then. (They are also one of the last trees to start showing signs of life in spring; they are slow to wake up).

After I prune in late spring the new buds take a while to get going and usually get to the length they are able to be pruned again by the end of the season. However, by this point it is too late to prune them again, so I just leave them to late winter.

This pruning will of course build ramification and denser foliage, but as you can see it’s slow compared to other trees that you can prune a few times a year.

Developing Boxwood as bonsai is certainly possible; it’s just a very slow process.

They will also back bud pretty easily. I have noticed all sorts of adventurous buds popping out from time to time.

However, there is a bit of confusion about how hard you can prune a boxwood. It is commonly said that if you remove all the foliage then the branch will die.

Personally I’ve not tested this and just try and keep some foliage on the tree, but at some point I will have to test this out to find out if it’s a myth of fact.  Knowing this information is going to help us grow these trees as bonsai more efficiently, so it is something that needs tested.

Is A Boxwoods Styling Ability Good For Bonsai?

Boxwood can really be styled in any way you want. They are just small shrubs, so do not really have a natural tree form. They are probably best suited to look like a big spreading broadleaf tree in an open field. This is the style I am going for, although I am pretty far off at the minute.

The only thing to be careful about is not allowing them to have too much long straight growth with balls of foliage on the end. This looks very below average and is usually how a beginner would try and style a tree. This look is very easily achieved with Boxwood growth habits, so be sure to avoid this.

Wiring

You can wire a boxwood with no problems. They can get a little stiff once the branch ages, but if you wire them while they are still young you should not have any problems.

You can also wire them right out to the tips to get your branches in the direction you want, which will allow you to then control your clip and grow growth more effectively.

Is Boxwoods Fall Colours Good For Bonsai?

Boxwood is evergreen so there is no change of colour throughout the year and there is no winter silhouette to enjoy.

This can be used to your advantage as no one will be able to see the structure properly. I believe my tree has a few sneaky T-branches hidden behind the foliage that have allowed me to make the tree look a little fuller than it would be if I removed these.

My structure might not be perfect, but the outer foliage will always look good.

Is A Boxwoods Bark Good For Bonsai?

The bark is actually pretty good on boxwood. It looks old and interesting, even from a young age. Of course the fact it is on a thin trunk is annoying, but apart from that, it can look great and you can easily hide wounds with the bark.

However the bark is thin, so while it looks good for bonsai, it can be easily damaged from bonsai techniques, such as wiring, so you will need to be careful.

Deadwood Opportunities

Boxwood wood is actually really hard. It was commonly used in wood carving and often used to make chess pieces, but as for bonsai, you can make deadwood from it and as it is so hard, it will not rot away easily.

Dead branches will probably not suit the tree in most styles, however, carving on the trunk would work very well.

Again the main problem is having a trunk thick enough to make this look good. If you are trying to carve a pencil thin trunk, it’s going to look silly.    

Are Boxwoods Roots Good For Bonsai?

I love the roots of boxwood, they are my favourite roots of all my bonsai trees. They are not super fine, they are a little fleshy, but they are just very well behaved.

They grow a lot more aggressively than the top of the tree and can fill a pot quite quickly. However, I have always found that they are extremely easy to untangle.

They do the usual trick of circling the bottom of the pot, but I have never been confronted with a solid mass that could not be easily untangled. I don’t even use tools; I can get everything sorted with only my hands.

They also respond well to pruning. You can hack them right back and they don’t seem to mind. Although they are not perfect, I would very much like more bonsai trees to have roots like a boxwood. I think they are great.    

Is Boxwood Easy To Care For As Bonsai?

Boxwood are also very easy to care for. They do not need any special treatment and are usually pretty hardy too.

Apart from being extremely slow growing, I have not had any problems with them. You can read more in my Boxwood Bonsai Care Guide.

Conclusion

Boxwood can be great for bonsai, especially if you can find an old tree with a great trunk. If you can do this, you are on your way to having an amazing tree. If you can’t find this, then you need a lot of time to let a small tree grow into something decent.

Their slow growth is painful to deal with, but apart from that they have a lot of potential. So long as you have patience, you will enjoy boxwood as a bonsai