Tuberous Begonia

(Second part)

Purchase only high quality, firm tubers. Tubers can be started early indoors one month before the frost-free date for your area in flats or pots filled with a 50:50 mixture of moist peat moss and perlite. The depressed side of the tuber should be facing up.
The tubers should be sprouted in the dark at 70 degrees F.

As soon as shoots develop, cover the tubers with more peat moss, and move to a bright location such as a sunny window. The young plants should not be transplanted outdoors until all danger of frost has passed. When planting, place the tubers just slightly below the soil line as they rot easily when planted too deep.

A minimum 18-inch spacing is recommended to allow the plants to fill out properly. After planting, do not cultivate around the root system or fibrous roots will be damaged. Since the stems are quite brittle, they often need staking, especially in windy areas. Plants should be watered when the soil begins to dry.

The tubers will rot if they are overwatered. Try to water in the morning if possible so that any moisture that gets on the foliage will have time to dry before evening. Wet foliage increases the chance of disease. Pick flowers off as the edges turn brown to prevent them from rotting and starting disease. If plants are dry and stressed and the leaves turn brown, the cause may be too much sun, too much heat, or too little water.

If plants are leggy, this means that they are getting too little light. White growth on leaves is powdery mildew disease. Fungicides can be used, but wider spacing and more air circulation may be all that is needed. After the first fall frost, dig the tubers and remove the foliage. Dry the tubers for a few days, and store them overwinter by placing them in dry peat moss or sawdust in a paper bag at about 50 degrees F.