Mirabilis jalapa or four o'clock flower is the most commonly grown ornamental species of Mirabilis, and is available in a range of colors. Four O'Clocks got their name because it opens in mid-afternoon. The botanical name Mirabilis is Latin and means "wonderful." It refers to the flower color. This plant is a longtime favorite that prefers full sun to partial shade and is very tolerant of heat stress and pollution.It remains open overnight, and closes in early morning. They will also remain open on cloudy days. They are also noted for their strong, pleasant fragrance. These flowers are very beautiful and can come in many different colors. Flower colors include white, red, pink, yellow, and some two-toned blooms.
Four O'Clock are typically grown from large seeds, making them easy to plant. Four O'Clock seeds germinate quickly, and grow fast, up to 2-4 feet. Sow seeds directly into the garden just before the last frost in your area. Cover seeds with 1/4" of soil. Space plants 12 inches apart and thin to two feet apart. In addition, Four O'Clocks is propagated by its tubers. Tubers should be dug up in the fall and stored in the dark, in damp peat moss or sand.
Four O'Clock prefer full sun, but will tolerate partial shade. Note that in partial shade they may grow lanky. They will do well in rich, well composted soil as they are big eaters. Keep soil moist. Add a general purpose fertilizer once or twice a month to encourage vigorous growth.
