Bonsai literally means “planted in a container”. It is the art of growing trees in a confined space to induce environmental conditions on the plant such as twisted or contorted form, age, and weathering. These are miniature trees, not dwarf plants.
First choose what type of tree and look you want. There are upright forms, cascading, and slanting with slight modifications within each style. Pick a plant that is already leaning toward the shape or form that you are looking for.
Shishigashira (Japanese Maple), photo by the Omiya Bonsai Art Museum
Clean up the plant
- Remove extra branches and stems that do not contribute to the design you are looking for.
- You want a strong trunk form, that means removing all the small branches around the base.
- The trunk branch should run from the bottom of the plant all the way to the top.
- The branches you choose to keep should be cut back if they are too large and out of proportion to the rest of the plant.
- Choose the side of the plant that will be the front of your pot and work from that side from now on. This should be the best part of the plant.
Pruning for shape and form
- The first branch of the plant should be 1/3 of the way up the trunk of the plant.
- From there, remove branches that do not contribute to the balance of the tree and wire branches to fill in spaces where there should be a branch and there was not. Note: Wire can damage the tree, use some type of cloth on the tree to protect it. The wire will come off when the branch has grown into your tree.
- Alternate the branches up the trunk until you reach the top.
- The tree canopy should form a triangle with the top of the tree being the highest point and the lower branches reaching the farthest out. Unless you want a different look!
Note: Older trees have horizontal branching and even droop downwards slightly. Wire the existing branches so they look mature and will grow in a horizontal manner.
Water and Sunlight
- Check the plant to make sure that it is dry. This will change with the season and maturity of the plant in its pot.
- Water the plant thoroughly so that water runs out of the drainage holes.
- Spray mist the leaves of the plant to clean them. Don’t spray the leaves in direct sun or at night.
- Most plants need partial light and cannot handle direct southern exposure sun. An east window with morning sun is the best environment.
Repotting
- Repot in early spring before any signs of growth.
- Remove excess soil from the roots and cut any roots that are thicker than a pencil to promote smaller feeder roots. This decreases the chance of girdling the roots.
- Trim the entire root ball and return it to its original container with fresh soil.
- Smaller plants should be repotted every 2-3 years. A soil mix should contain equal parts of sand, peat moss, and perlite.
Winter Care
- Gertens sells indoor plants for bonsai, which can and must stay indoors all the time.
- Plants such as maples and evergreens that are outdoor plants, need a dormancy period at least once a year and will need to be put in a room or cold frame outside that can be kept between 33 – 40 degrees. An unheated garage is a good place to store the plants or you could bury them outside in their pots, cover them with mulch, and cover with a cone to keep the roots from freezing and killing the plant.
- Do not work on the plant inside during the winter because it might break dormancy. Once the weather warms in spring, bring the plants out gradually and expose them to moderate amounts of sun at one time.
Bonsai Tools and Uses
- Shears. You need a pair of sharp scissors which will allow you to do the fine work of trimming in a small space. Use them only for bonsai work. It’s best to use shears made especially for bonsai work.
- Concave cutters are essential. They allow you to cut branches off the tree and leave behind a concave wound which heals much faster than a straight cut. The cut will callous over in a way that makes it very difficult to tell that a cut has been made at all.
- Bonsai wire cutters are also essential. If you put wire on, you will eventually have to take it off. These wire cutters allow you to cut the wire right up to the tree's bark, without harming the tree.
- Wire. You will want to get several different thicknesses of annealed copper wire. It is very flexible until it is bent, then it sets and holds its position. You will use it to position and train branches.
- Knob Cutters.These are very similar to the concave cutters listed above, except that they have a spherical head, which allows you to cut branches and leave a small hollowed out scar. This is very useful, but not as important as a good set of concave cutters.
- Folding saw. This is a useful tool for cutting through branches larger than the diameter of either concave or knob cutters. This is particularly important for working with big trees.
For more information, ask for assistance from one of our Gertens customer service representatives. If they don’t know, they’ll find someone who does!
The experts at Gertens are always available to answer your questions!