Image Source : http://www.burpee.com/flowers/four-o-clocks/ |
The flowers usually open from late afternoon onwards,hence the first of its common names. They produce a strong,sweet-smelling fragrance throughout the night and close for good in the morning. New flowers open the following day.
Four o'clock flowers are plants whose leaves are not complete because they only consist of leaves and stalks. The edges of the leaves tend to be average or integer and face opposite each other. The leaves are classified as even pinnate compound leaves. The stalks are round and grow straight up. The roots are sole and white. Despite their appearance,the flowers are not formed from petals-----rather they are a pigmented modification of the calyx. Similarly,the 'calyx' is an involucre or covering of bracts.
The flowers are pollinated by long-tongued moths of the sphingidae family,such as the sphinx moths or hawk moths and other nocturnal pollinators attracted by the fragrance.
This flower hails from tropical South America,but has become naturalized throughout tropical and warm temperate regions.In cooler temperate regions,it will die back with the first frosts,regrowing in the following spring from the tuberous roots. The plant does best in full sun. It grows to approximately 0,9 m high. The single-seeded fruits are spherical,wrinkled and black upon maturity,having started out greenish-yellow.The plant will self-seed, often spreading rapidly if left unchecked in a garden.