| by Keith Stevens, Senior Horticulturalist |
Spring is almost here! As I write this, the snow is still on the ground and I’m thinking of all of the bonsai trees that are dormant waiting to start blooming in a few weeks. Now is a good time to start preparing your bonsai trees for the spring and depending on the types of trees you have, it is a good time to prune. Deciduous trees, ones that lose their leaves in the winter, can be pruned while dormant. With no leaves is much easier to see the branch structure and where to make cuts. Evergreens can be wired at this time too. Check your trees for any wires that may be girdling branches. Either remove them or replace them.
Start deciding which trees will be repotted in spring. Make a list of available pots, and which trees will work with them. Having a battle plan is very useful once the chaos of spring arrives. You should start ordering repotting supplies such as new pots, soil, wire, drainage mesh, etc. It’s best to repot closer to the end of March.
During the winter months water only when the soil is dry. Try not keep them too wet. Soil will stay moist for several weeks before needing water. I like to still check often just to be sure. Keep in mind that roots do better in moist frozen soil than dry frozen soil. Protect your trees from direct winter sun and wind as it will cause freeze dry damage.
Trees start into growth in spring when temperatures rise above 50°F for a period of days. They are not prompted by increases in light levels. It is important that as trees start to grow they are placed back outside where they have access to light. However, late frosts in spring can devastate tender new growth and on nights where frosts are forecast, temporary protection must be afforded. I’ve found early spring you will find moving trees from inside to outside for a few days. In our area about mid to late April you can safely move them outside. Any tropical plants should stay inside until the temperatures are well above 50°F, if you wish to take them outside.
This year the bonsai show will held on May 30. This is in conjunction with the reopening of our Japanese Garden. The bonsai show hours are 10am to 8pm. Hope to see you there.