Wooden growbox for bonsai, why?

Yesterday I built a few wooden growboxes to repot my future bonsai trees in next year. I put a picture of them up on facebook in a bonsai beginners group and immediately got a few questions from people who were wondering why in the world I would put my trees in big chuncky wooden growboxes and not in a nice bonsai pot.
So that’s why I’m making this post.

First here are the boxes I built so far over the last couple of weeks.

6 for myself, 2 for a friend

Basicly, people use wooden grow boxes for trees in development. It doesn’t replace growing trees in the ground but it duplicates some of the benefits from ground growing. It even eliminates some of the disadvantages from ground growing.

Here are some advantages of growing in a wooden box compared to growing in the ground or a plastic/ceramic container.

• Like with ground growing roots have more space to grow so the tree grows stronger, branches in development will reach their desired thickness much faster.
• Unlike with ground growing the watering can be controlled and trees can be moved.
• Because of the wood there’s more insulation compared with plastic/ceramic containers. Less cold in winter, less hot in summer.
• The soil doesn’t dry out so fast because the woods retains moisture longer than ceramic/plastic containers.
• Because grow boxes are usually quite flat roots can be spread out better and won’t grow downwards. Which will benefit the development of a good nebari.
• It’s possible to attach the tree and/or roots to the bottom of the wooden growbox to control the direction of the growth.
• It’s also cheap to build a growbox. I mostly use wood I recover from various sources.
• You can make them any size you want.
  

Some of the questions I encountered were:

Q: What kind of wood do you use? Most wood can’t handle lots of water for years in a row.
A: I just use pine wooden planks. They last 3-5 years before the box falls apart. By that time the growbox has served it’s purpose and the tree is usually ready for it’s next phase of development.

Q: Do you put something else in the box, like plastic foil? Otherwise the water will probably run out and make your table all dirty.
A: The soil goes straight in the wooden box. These boxes stay outside or in a greenhouse for the entire year. Water should run through like with any bonsai container to prevent the soil from staying too wet and to ensure that there’s air circulation. Otherwise root rot will occure. Trees don’t belong indoors, they won’t thrive there and will die eventually. Also it’s beter for your kitchen table.

Here’s some projects of mine that are in wooden growboxes:

One of my biggest trees, an Acer Campestre.

A fagus Sylvatica forest. The trees stay in this box for 2-3 years to let the forest “become one”. After that it goes on a slab or in a bonsai pot.

This 3 year-old Acer Palmatum seedling was put in a growbox earlier this year. It can stay in ther until the box falls apart. in the meantime a Moyogi tree is in the making.

This Acer Palmatum is in it’s box for 2 years now. The nebari is starting to look good. Wounds have healed very nice and the branches are coming into place. I hope the box to last for another year. After that the tree can go in it’s first real bonsai pot.

Lots of people still want to put their tree in a bonsai pot before it’s ready for it. That’s why we see a lot of sticks in bonsai pots on the social media and forums. It takes years to develop a good tree and the wooden growbox certainly is one of the good steps to take if you want to have a tree that really stands out from the crowd.

Any questions? Don’t hesitate to ask.