Outdoor: Be ready to put your trees into winter protection as soon as the weather dictates the need for it. A night temperature of 25°F is a good reference point as to when the trees need protection. Remove remaining foliage on deciduous trees and any weeds or debris on the soil before placing the trees into winter protection. Spraying with a general fungicide can be beneficial. Keep your trees well-watered. The trees will use less water in cooler temperatures. Fertilization may be stopped at this point. Do not repot except in the case of an emergency. Wiring may be done and is often easier to do on deciduous trees after the leaves have fallen.
Indoor: Provide maximum amounts of light during the fall and winter seasons. The use of artificial light may be needed. Fertilize trees growing under artificial light. Water as needed for your indoor conditions (light, temperature, humidity).
REFERENCES:
Editor. (Volume X, Number 10, 2003, November). Things To Do This Month. Bonsai Hai. Prairie State Bonsai Society.
