I know spring is just around the corner when I prepare my begonias tubers to spend a few months in the greenhouse. They have been stored in the garage, a frost-free environment. Begonia tubers are available this time year at local garden centers. Begonias are shade-loving plants and will provide spectacular displays of continuous flowering from June to early fall.
Selecting a good tuber, you will note the center will show signs of life in the form of pink tips. The container or pot used is according to the size of the tuber. Fill this pot three quarters full with moist peat and perlite mix. Firmly place the tubers into the pots with the new growth up and then cover with ½” of peat mix. Using the propagation bed, the bottom heat will encourage root formation and stems will sprout. It is important to keep the growing medium moist but not wet. A few hours of supplementary light with grow lights will give the begonias a head start.
Once there are a couple of inches of leaf growth, gently lift them and re-pot them into their final container or basket. Begonias prefer a soil mix that drains quickly. The baskets or pots will thrive in a bright location in the greenhouse. As the spring season becomes sunnier, these plants will require a light but shadier area of the greenhouse.
It is interesting to note that begonia tubers will substantially increase in size during the summer months. My begonia tubers have become quite large over the years and I have divided them. When I take them out of storage, they are dry and so it is easy to cut or divide the tuber. Sometimes a piece will break off, which is potted on as a new tuber. Chances of success are better if this piece has a growing tip.
- Clean all pots, containers, and baskets with hot water and a disinfectant like Lysol or a few drops of bleach.
- Mildew on begonia leaves is caused by lack of air circulation. When this occurs, the affected leaves must be removed and the plant relocated in the greenhouse.