Chocolate Plants (Pseuderanthemum alatum)
"Chocolate Plants" (Pseuderanthemum alata) are a beloved heirloom plant in Texas and other parts of the South. Like 'candlestick plants' (Cassia alata) with their big spikes of golden flowers or 'air potatoes' which are vines that are members of the sweet potato family, Chocolate Plants are almost never found in catalogs. They're usually carefully nurtured by individual gardeners and distributed through family and friends, unless a person is alert enough to find some at a small local Mom-and-Pop nursery.
"Chocolate Plants" Pseuderanthemum alata
The association of the word 'chocolate' comes through the shades of reddish brown interspersed with silvery patches that are never quite the same on individual plants. Extra silver dots are splashed over the resulting low growing mound of subtle color. The leaves are broad and the entire plant is from six inches to a foot tall and perhaps a foot or a little more wide. Unfortunately, the word 'chocolate' does not refer to a smell or taste of chocolate associated with the plants.
Chocolate Plants are members of the Acanthaceae family, and were originally native to Mexico and Central America. Their family also includes such famous garden stalwarts as acanthus, a favorite of the ancient Greeks and Romans, and modern-day tender favorites such as shrimp plant (Justicia brandegeana), fireman's cap (Odontonema), Persian Shield (Strobilanthes), wild Mexican petunia (Ruellia), Polka-Dot plant (Hypoestes), Bush Violets (Barleria), Chinese Hat (Megaskepasma), and Lollipop plant (Pachystachys lutea).
Chocolate plants seem to be able to survive cold a bit better than most of the relatives listed above, with the exception of the shrimp plant and fireman's cap, which are also usually hardy through Zone 8.
Although the tops will freeze down during the winter, most plants readily come back the next spring and can last for several years. The slender one-foot to one and a half-foot bloom stalks havel purplish-rose flowers and make enough seed to ensure that there will be a sprinkling of new chocolate plants the following spring. They are also propagated through cuttings.
If the tiny seeds are collected in the fall, they may be sown in the spring in light propagating media. They are said to germinate best after 21-25 days at 55-60 degrees F (13-15 degrees C).
Chocolate plants are a great groundcover for partially or fully shaded areas. Although they enjoy moist soil, they are actually quite tolerant of dry places and rebound quickly after wilting in between rainfall or irrigation.
If they are kept as 'porch' or greenhouse plants, pot them in a well draining mixture of peat, garden loam and sand/or perlite. Fertilize weekly with a mild solution of fertilizer, and be sure to let them dry out a bit between waterings.