How to Grow a Bigger Bonsai - Faster

Ongoing care of your bonsai is really a matter of training, feeding, watering, repotting and continuing in your efforts not to kill it. No one article can fully cover the subject, so we’ll break it down and for today let’s focus on one question:

Do you want your bonsai to be bigger, smaller or to stay the same size?

The nice thing about this subject is that it doesn’t make much difference if you're growing trees that winter outside or trees that won’t survive your winter, which is technically the definition of outdoor versus indoor trees.

I want my bonsai to get bigger!

Unless you work to prevent that, as long as you can keep it alive, your bonsai will inevitably get bigger. But left in a bonsai pot and trimmed so that it doesn't look like my "lock-down"  hair, it will take a long, long time.

Most people who want a bigger tree, don’t really want to wait 15 years to notice a difference, so here’s the secret: Take it out of the bonsai pot!

You have options: either move it to a bigger pot or plant it into your garden and just for the record, unless we’re talking about trees that resent being moved around a lot ( Ficus and Eugenia (brush cherry)) spring to mind, you can plant trees that winter indoors outside in the ground for the summer. Just be sure not to plant your moisture loving Serissa in super hot, dry ground, and do protect your trees from the lovely little bunny that does not look so lovely after it strips the bark from your Chinese Elm.

Juniper Procumbens nana - I named her Daria and she has doubled in size so far.

This tree is a juniper procumbens "nana" - exactly the same juniper as sold on ZenGardenBonsai. I named her Daria and wanted her to get bigger so I took her out of the pot and stuck her in the ground 2 years ago ( bonsai needs patience). Unlike many trees that will survive winter indoors, this juniper can stay outside year round.



Two Elms

Here are two Chinese elms- same age and almost the same care, except that the tree on the left spent about 18 months in an oversized pot, heavily fertilized and allowed to grow in any direction it wanted. Once it hit the size I wanted, it was trimmed and root pruned back into a bonsai pot where is now behaves most politely.

You will, of course, need to dig it up around September and repot it for the winter, but unless it’s put on enough of a growth spurt to satisfy your desire for a bigger plant, don’t put it back into a bonsai pot yet. Plant it in a pot that you would use for a house plant so that you don’t need to trim the roots back- yet. For the winter give it the best light you can and be very careful not let it sit in water.

If you choose to simply move your bonsai into a houseplant pot, choose something bigger than you would normally use ( but not too big or it will hold too much water).
What kind of soil? Go with a lightweight potting/seed starting mix amended with PERLITE or a cactus mix. Do not use garden soil, top soil, triple mix or anything heavy in the pot.
If possible, put the tree outside for the summer.
Feed heavily. Use any type of fertilizer, but try for something balanced like a standard tropical plant food and push to the max for the summer.
Don’t prune, unless you’re pruning to correct a structural issue - and that’s the subject of a much more complicated post. But think of this- as the branches on your tree elongate, they will accommodate more foliage, which will photosynthesize, producing more sugars and starches that will feed your tree. More leaves and more branches draw more nutrient through the trunk and those same branches, causing thickening. Your tree will look shaggy, but it will expand much faster than it ever would as a neatly trimmed bonsai.