Sunday, January 8, 2012
Cleome hirta, an African cleome
I got seed of this a few years ago from JL Hudson, and it is one of my favorite annuals. It is hard to photograph because it is an airy plant, not dense and showy in the typical sense of many garden flowers. It grows fast in warm weather, and sets copious amounts of seed in long thin pods. Unlike the common garden cleome, it is not annoyingly prickly stemmed. I like the unusual yellow markings which contrast nicely with the light purple base flower color. The flowers are great favorites of bumblebees, and C. hirta will flower for a long period of time from mid/late summer till frost. For earlier flowering in northern parts of the US, it is best to start it early indoors, as is the case with Ceratotheca triloba, another African annual worth growing.
There are several other species of Cleome in southern Africa, but I have yet to have success in germinating the yellow flowered ones. I assume they have some kind of inhibitor present in the seed, or they may require special treatment such as scarification. I will keep trying to get them to germinate, as the yellow flowered African species can be quite spectacular in flower.