Monthly Tasks - December

Based on San Francisco Bay Area Climate by Mitsuo Umehara

Early December

  • Deciduous trees - To enjoy the fine silhouette of deciduous trees, cut just enough back to restore the shape. The more drastic shaping can be done in the spring.

  • Group Plantings - This is the time to scrutinize your group planting. Is the group shape as it was originally designed; the height; the flow; the direction? Do the corrective work now while the branches are bare. Pay particular attention to the crown or apex of each tree in the group. Don’t allow too many branches to grow from one place or node on the tree. If wired, the wire should be removed in the spring.

  • Conifers - Trees such as black pines, five-needle pines, and yew trees are cold weather tolerant and can be wired through the winter until the buds start to develop in the spring. However, they should be protected from the severe weather after they are wired.

Mid and Late-December

  • Ume -After an ume has been exposed to the first frost, bring it into a warm place and mist spray it daily if you want blossoms for New Year's Day. The flower buds should start to develop within two weeks.

  • Watering - Remember that as the weather gets colder the humidity also drops. So, if it's not raining you still have to water. The dryness of your trees should be checked closely; but watering every third day is the rule of thumb for this time of year. When the winter rains continue:

    1. For those transplanted in autumn, tilt the pot to provide better drainage

    2. For those transplanted in November, cover the pot with plastic. Remove the cover as soon as the rain stops.

    3. Keep moss growth under control. If you leave large thick pads of moss in your pot during the rainy season, it is likely to grow up the trunk of the tree. This can damage tree bark and invite fungus. A good idea is to reduce moss growth on all trees through the rainy season.

    4. Cleanup - On a clear day, clean the shelves, pull weeds, and rotate the pots. Inspect each tree carefully and make notes to record progress for future reference.

    5. Trees displayed at Christmas and New Year's -Sho-Chiku-Bai (pine-bamboo-ume) are the symbolic plant combinations the Japanese use for New Year. But any bonsai can be displayed for the holiday season. It is a real treat for visitors to see live trees and plants in the middle of winter. So put your creativity to work and have fun with your bonsai during this special time of year!