Shrubs and Small Trees - Seasonal Care !

Watering Fertilizer Coldframes

Coldframes

It is easy to construct a simple coldframe for bonsai. Before the ground is frozen, dig a hole at least 1-1/2 feet in the soil. Make the hole as long and as wide as you need for all your plants. Line the sides of this hole with exterior grade plywood, which extends 6 inches above the surface. Put 4 to 6 inches of gravel in the bottom of the hole, set your plant containers on this gravel, and spread straw around and over them. Put a loose-fitting cover on the frame made of polyethylene sheeting or any similar material.

Watering

In the summer, during hot weather when the temperature is over 90 F degrees, water the bonsai plants one or more times a day. If the plants are in an unusually sandy soil, they will require watering three or more times a day.

In early autumn, follow the watering directions for late spring. In late autumn, follow the watering directions for early spring.

In winter, keep the trees in a coldframe and ventilate the plants on one or more sides to keep them dormant. Check for dryness every 2 weeks. Water the plants every second day, or less, as required. Keep in mind that far more bonsai are killed by overwatering than by a lack of water. 

Fertilizer

To maintain plant growth use fertilizer to supply nutrients. Maintain the nutrient level in the soil mix throughout active growth with monthly applications of a diluted liquid fertilizer. Apply fertilizer only before and during active growth. For a liquid fertilizer you can use a typical house-plant fertilizer (20-20-20 or its equivalent) diluted to one-quarter strength on the label.