Bonsai from Garden Centre or Supermarket Material
The best place to buy starter bonsai material is a bonsai nursery; however, if you are not within striking distance of a bonsai nursery, you can find suitable starter material at you local garden centre, or even supermarket, it will require an extra season to develop. This material will often consist of cuttings, grafts, and seedlings of trees such as, Chinese Juniper, Japanese Larch, crab apple, Japanese Mountain Maple, cotoneaster, and hedging beech, etc. These trees will not have been transplanted and root pruned, and few, if any, fibrous feeder roots will have formed, instead, there is usually a root bound coil of roots, sometimes so old as to be woody.
Supermarket material will usually be root bound and growing in waterlogged compost, often, pure peat. They are most often growing in 3-inch pots; garden centre material will usually be of better quality, and in better quality compost, but still tends to be root bound and over watered.
The tree on the right was bought from a supermarket spring 2009 in the square pot on the left for £2.99. It was pruned; the stub to stop die back is still visible, and planted into the 5-inch half pot. I took ten cuttings off the pruned bit and by summer, seven had taken, one is in the pot on the left. We’re having a late spring here in England, but I think these will be ready to work on by the end of March, beginning of April.
When you get your purchase home, don’t be in a hurry to style it, and don’t try to tease out the roots, just carefully cut about one third from the bottom of the root ball and trim the sides. Sometimes, if you are feeling brave, or if the material is particularly vigorous, it is possible to cut alternating pie slices out of the side of the root ball to encourage stronger inner growth. Transplant into a mixture of potting compost, sharp sand and aquarium gravel; please, not the coloured stuff, if your pet shop doesn’t have natural, find another pet shop. Plant in a 10-inch diameter clay half pot, or a large washing up bowl with good drainage holes drilled in the bottom, anything where the width is greater than the depth, will do, as long as it has good drainage.
Planting in light, sharp, open compost allows the roots to spread rapidly and has the effect of loosening and draining the old root bound wet mixture. This rapid, and easy, spreading of the roots, allows the trunk to start thickening at the base with the thickening roots. Site the tree in a sheltered are of your garden, somewhere that gets morning and evening sun, but is sheltered from the sun during the hottest part of the day; keep the compost evenly moist. The best time of the year for this work is spring.
Things to avoid in the garden centre or supermarket:
Big trees in big tubs, it is possible to cut them down and make bonsai from them but it requires a lot of skilled, experienced work.
Those cute looking ‘indoor bonsai’ in their green pots and trays, they generally need a lot of extra work to make them acceptable to the trained eye. They come from areas that have different light and humidity to the average front room, and often they need bottom heat to revive after transplanting.