Forest in a pot

Growing trees and shrubs in pots around your condo or townhome deck saves space, money and time

For Mike in Lethbridge, it started as a rescue operation.

He found dead-looking shrubs in the garbage behind stores and homes. He revived them, not as full-sized trees, but as miniature, windswept versions of their bigger selves.

His rescues became bonsai, and he built a delicate forest of trees in tiny pots.

Before I met Mike, I had never seen a crabapple or potentilla in a bonsai pot.

Why bother with bonsai? While a crabapple tree at 10 metres tall is a big tree, a 60-centimetre version in a bonsai pot is the perfect size for a patio. And the brilliant red crabapples, 1.5 centimetres across on a full-sized tree, are still the same size on a bonsai version of the same tree.

But Mike's little pots in his back yard are a lot of work. They require extra maintenance during the season and considerable effort to overwinter.

Still, if you live in a small residence you may be interested in stealing a page from Mike's handbook and shrinking plants, even if they are not bonsai-perfect, to fit into your yard and small space. You might be able to grow a forest, even if all you're working with is the space of a condo patio.

Will Plants Survive in Pots?
Ceramic pots could crack from continuous freezing and thawing of water in the winter, and plants within them might not fare any better.

However, Kathy grows a woody kiwi vine (Actinidia sp.) in a ceramic pot in Calgary beside a north-facing back door. My friend Caenie grows a false spirea shrub in a pot overwintered outside her north-facing front door. The common theme here is north-facing and close to a door. The pots don't freeze and thaw because they are in the shade and under cover of the roof. The plants are able to survive in these cold but stable conditions.

If you live in a small residence you may be interested in stealing a page from Mike's handbook and shrinking plants, even if they are not bonsai-perfect, to fit into your yard and small space. You might be able to grow a forest, even if all you're working with is the space of a condo patio.

I planted a weeping caragana in a 75-centimetre, square, wood planter insulated with rigid foam. This dwarf tree is interesting without needing ground space. The wooden box shrinks and expands instead of breaking, even though it is exposed to an east and south exposure.

Adjusting Soils
Mixing natural garden soil with lighter, purchased soil is better for woody plants in outdoor pots than all-natural soil. Keep the plants healthy and encourage slow growth by adding an inch of high quality compost or worm castings on top of the soil each spring.

Trimming
Whether you are growing a bonsai or just a small plant, you have to keep it trimmed and in proportion to the pot. For true bonsai, plants are trimmed often and this keeps the roots small. Trimming after leaves open is better for spring blooming plants like apple and lilac. Use a small pair of sharp shears to shape, rather than rip, branches on the tiny tree.

Watering
The key to bonsai and other forms of miniaturized plants is water – keep soil moist, not soggy. Plants like a shady spot and misting, or light watering, daily.
A tree kept overwinter gives you bragging rights. You are clearly a fabulous gardener even though your space is limited.

Donna Balzer's column appears exclusively in CREB®Now biweekly. Contact Donna at www.donnabalzer.com

Tagged: container gardening | Donna Balzer | Gardening | Guest Column