“I have about 150 bonsais growing in my back yard.” – Cindie Duke Bonomi
Tree Calendar: Seasonal Tips -Spring
- What your trees need from you this spring:
- Clean tools with WD40, which removes sap and lubricates moving parts. Clean pots before you place trees in them.
- Deciduous trees can be re-potted when the leaf buds start to swell and extend. It’s a short time frame, so if the buds start to open into leaves, it’s too late. Place wire screens over the holes in the bottom of the pot and wire in place, so the soil doesn’t fall out when watering. Wire the tree firmly in the pot through the bottom holes to make sure the tree doesn’t move in the wind and break the newly forming roots.
- Conifers can be repotted when the buds start to move and white tips are showing on the root ends, usually after deciduous trees.
- If root pruning, cut off longer tap roots and enough outer roots so that the tree fits in the pot with room to grow. Cut back any dead areas. Any larger roots can be cut over the course of several years, with the idea developing a network of small, hair-like feeder roots.
- The ideal potting medium is Japanese Akadama, a clay product imported from Japan. It can be mixed with pumice and lava in different proportions depending on the variety of tree and what needs to be done to the tree. If Akadama is unavailable, use a course soil mix of Hadite or pumice and dried pine bark pieces (all materials screened to remove fine particles). A mix of 3-4 parts Hadite to 1 part bark is good for conifers, half and half for deciduous, and more than half bark for tropicals. For very small pots and fine root development, a smaller particle will allow roots to grow and hold in a bit more moisture. Use a chopstick to gently poke in the soil and remove any air pockets.
- If you are wiring any branches, do so before repotting when the tree is more stable in existing pot.
- After repotting, soak tree in a shallow pan of water for 20 minutes and place in a protected, shady site on the ground for a few weeks to recover. Don’t over water since the plant is not taking up much water on its own.
- Fertilize after a month or so when the tree has adjusted to the new pot.
REPOTTING DECIDUOUS TREES
4 Stages of Budding
1. Dormant bud stage – When the buds are tight on the branch, trees can be collected from the wild or lifted from the pot. Do not root prune or you will be cutting away stored energy.
2. Swelling buds – Coming out of dormancy, it’s o.k. to repot or root prune.
3. Extending buds – Best time to repot and root prune, a short time frame.
4. Open buds – Usually at the top or on branch ends, it’s too late to prune or repot.