Caring for Begonias Overwintering Indoors
Why do my begonia plants die every winter? I keep them in containers and move them indoors when cold weather sets in. Should I set them in a sunny location?
Though begonias are shade lovers in the outdoor garden like most annuals they need a sunny window or artificial lights to survive indoors. Gradually move the plants from their perfect outdoor growing location to the lower light and low humidity of the indoors. Grow in a sunny window or 6 to 12 inches below a set of artificial lights. Give the plants plenty of space to grow. Low light combined with poor air circulation (from overcrowding) increase the risk of powdery mildew. This fungus forms a white powdery surface on the leaves. As the disease progresses it prevents the light from reaching the leaves causing them to yellow and eventually brown. Good light and sufficient air flow is usually enough to keep this disease in check.
Water the plants thoroughly pouring off the excess water or collecting it in a pebble filled saucer. This avoids root rot caused by plants sitting in excess water. Using the pebble filled tray method also helps increase humidity around the plant. The pot sits on the pebbles above the water. As this water evaporates it increases the humidity around the plant where it is needed. Wait until the top few inches of soil are crumbly and moist before watering again. Only fertilize healthy actively growing plants.