June 2007

Begonia valida

Charles Jaros tells us of this month's plant, and supplied this photo of the seasonal variegation that is unique to the species.

Begonia valida, a species from Brazil, is classified as thick-stemmed, bare and large leafed. Its flowers are often fragrant. K Goebel published the plant desciption in 1915. This species is not commonly cultivated, but it is a relatively distinct plant. In South Florida, it makes an outstanding landscape plant and can grow to 6 feet or more. As the stems develop they will often have the tendency to droop over and root at the nodes when contacting the soil. This will create a bushy plant (which is not typical of thick-stemmed species). As it reaches height, B. valida will produce stems that are trunk-like in appearance and very thick--as much as 3-4 inches. B. valida has one curious feature that sets it apart from other thick-stemmed species: it will tend to variegate during the summer months. This phenomenon usually begins in mid-May and will last through the summer. With higher light levels, a green-white-pink variegated occurs. Foliage that has already developed green will not variegate. It only happens on new emergent leaves as stays as they mature. During the onset of fall, the new foliage reverts back to the normal green. Not much is known as to why this occurs. Speculation is heat and longer daylenths play a role in variegation. This quirk of B. valida is not unique to Florida. Begonian editor Freda Holley has also noticed it on her specimens.