Capsicum is the genus of ornamental plants. Capsicum annuum is the botanical name of species of ornamental peppers which are annual plants which are excellent for border plantings as well as for growing as a potted house plant.
Ornamental peppers are compact and grow into small bushes 12 to 18 inches high and as wide. Their dark green leaves are topped by bright-colored fruits that form in July and hold on the plant until frost. Depending on variety, fruits may be red, purple, yellow, or orange; the shapes range from conical to slim and tapered. There are even twisted forms. The small, white flowers that appear prior to the fruit are pretty but inconspicuous.
The heat generated by hot peppers comes from a mixture of different capsaicins. These compounds are sensed by the pain sensors in your mouth - the ones that tell you when the coffee is too hot - not by your taste buds. The amount of capsaicin produced is under both genetic and environmental control. A tormented breeder can do wonders to turn up the heat, but droughts and high average night temperatures also increase the capsaicin level.