The Begonia Genus

By Kimberly Labno 

Rex Cultorum

Begonia is a huge diverse genus with over a thousand 

different species. The genus is represented by various groups including:  Semperflorens, Rex-cultorum, Rhizomatous, Tuberous (Multiflora and Pendula), Cane-stemmed, Winter-flowering, and Shrub-like.

Caring for your begonia is simple. Keep the soil moist not wet, bright light not direct sun, pinch the flowers and as far as fertilizing begonias is concerned, the general rule is to go lightly. 

In terms of caring for the plant when winter arrives, it boils down to whether one has a fibrous root, a tuber, or a rhizome. If you live in a cold area, you may want to grow semperflorens (wax begonias) in     pots so you can bring them in when it gets cold. 

Rhizomatous Mix

Many times Rex-cultorum is grown as an annual bedding plant. Watering “on demand” (or when the soil is dry to the touch) is a great way to keep Rex begonias happy. Avoid soggy conditions, but do not allow plants to wilt. Give Rex begonias a diluted dose of organic, soluble food every four to six weeks during the growing season. Begonias do not grow or use fertilizer efficiently below 58°F.

Rex begonias make excellent houseplants and can easily be overwintered indoors. To supply plants with adequate humidity, place containers on a tray of gravel, where runoff water may collect, evaporate, and raise the air-moisture level. Avoid placing plants near drafts.

Begonia tubers cannot remain in the soil over the winter in very cold climates. Wait until after a killing frost, and then dig up the tubers. Shake off any excess soil and let them dry in a warm spot for several days. Cut off any bad spots and then carefully pull the roots, stems and leaves off the tuber. Wrap each tuber in a brown paper bag or wrapper and put them in a cool, dry place for the winter.

B.Benitochiba

Since there are so many varieties, learning proper begonia care is often a matter of learning from experience. As with any plant, inspect for insects before bringing it indoors. Also, be mindful of maintaining proper humidity because indoor humidity is much drier than out of doors.  For more details on begonias of all types and their care, the following sites are wonderful resources.

http://begoniacare.net/

http://www.gardeningcentral.org/begonia_care/begonia_care.html

http://www.begonias.org/Articles/Vol47/CaneLikeBegonias.htm

http://www.provenwinners.com/learn/overwintering-begonias
http://www.national-begonia-society.co.uk/index.htm