Home > Begonian > Volume 47 (July 1980)

The immense, diverse world of begonias

There is a begonia for just about any growing condition short of a lightless closet.

Begonia vitilolia will grow as tall as a house, while B. prismatocarpa is a creeping 2-inch plant. Many hybrids in the semperflorens classification take full sun, but B. pavonina requires deep shade. B. grandis ssp. evansiana is cold hardy, while B. versicolor requires the contained atmosphere of a terrarium.

The plant genus Begonia probably is more diverse than any other. More than 2,000 species and cultivars are grown today for foliage as well as flowers, and additional species are being discovered and cultivars developed each year.

A great number are easy to grow -- others are challenges requiring special potting mixes, high humidity, just-right light, terrariums, temperature control, or an unusual fertilizer program.

To make it easier to know how to treat them, begonia hobbyists classify begonias so that those with similar growth habits and requiring similar care are grouped together. This horticultural classification system -- different from the way systematic botanists classify plants -- was pioneered by several early plantsmen, compiled by ABS, and refined by Mildred and Edward Thompson of Southampton, N.Y., in their Thompson Begonia Guide. Millie was named ABS' classification chairman in 1980.

The main classes of begonias are cane-like, Rex Cultorum, rhizomatous, Semperflorens Cultorum, shrub-like, thick-stemmed, trailing-scandent, and tuberous. (Don't worry if some terms seem cumbersome. They'll be second nature to you in no time.)

We don't use -- and we want to discourage -- such misnomers as "fibrous begonias," " wax begonias," and "bedding begonias." We don't even talk about "watermelon begonias" or "strawberry begonias," which aren't begonias at all.

Besides knowing the classes, accomplished begonia collectors make it a point to use proper names. The right name ensures that when you mention a begonia to a hobbyist anywhere in the world, he or she will know what you mean.

Every begonia you own should be labeled with the correct name. A species name is not capitalized -- as in the example Begonia schmidtiana, which can be shortened to B. schmidtiana. Cultivars (cultivated varieties) are labeled with the genus name plus the cultivar name, which is capitalized and enclosed in single quotes: B. 'Ricky Minter'. Some species have varieties: B. conchifolia var. rubrimacula.

Be careful to use the single quotation marks and capital letters only for cultivars. Cultivar names are almost always in a modern language, usually English, while species are named in Latin.

When you became interested in begonias, you joined a long line of enthusiasts dating back three centuries. The name Begonia was first used by plant explorer Charles Plumier for the six species he discovered in the West Indies in the 1690s. The name honored botany patron Michel Begon, a French government official who arranged Plumier's trip.

in the 18th and 19th centuries, begonias grew to be popular house and conservatory plants in Europe and America. Introduction of bold-leaved B. rex into cultivation and hybridizing in the mid-1800s boosted interest in begonias as foliage plants.

Today, people grow begonias in the house, under fluorescent lights, under semi-shady patio covers, in the ground, in greenhouses -- anywhere they can find space. Keep reading and you will find out how you can, too.

Eight begonias representing the diversity of the genus came from the collection of Joan Coulat of Sacramento, CA. Arranged and photographed by Chuck Anderson and Karen Bartholomew.
Clockwise from the upper left:

• B. 'Gene Daniels'
• B. 'It'
• B. bowerae var. nigramarga
• B. metachroa
• B. species ex Kew
• B. polygonoides
• B. 'Clara Elizabeth'
• B. 'Purple Petticoats'(center)