Phoenix dactylifera or Date Palm is an economically important tree and one of the oldest cultivated crops in the world. Dates originated in Western Asia and North Africa over 5,000 years ago. Today they are cultivated commercially in Iraq, North Africa and in the U.S. in California and Arizona. The trees are dioecious and often reach over 100 feet (30 m) tall or more with a gray slender trunk. Trunks are patterned with diamond shape leaf scars. The large greenish to bluish gray pinnate leaves often reach 18-20 feet (5.5-6 m) long. The canopy can be up to 40 feet (12.2 m) wide. Although they are very large trees, they can be grown in containers for many years before they get too large. We have been growing ours for about 4 years and the plant is very slow growing. It has only attained a height of 5 feet (1.5 m) tall. They are of easy culture and hardy in the landscape in USDA zones 9-11.
Blooming: Our tree in the greenhouse has yet to bloom, as it is still fairly young. Dates bloom in the spring with 4 foot long inflorescences. It takes both female and male trees to produce fruit. Dates are purported to be the first plant in which the importance of sex was recognized. Ancient Babylonian tablets portray male inforescences being applied to female flowers by both men and gods.
Culture: Phoenix dactylifera need full sun with a well drained soil mix. In the greenhouse, we use a soil mix consisting of 1 part peat moss to 2 parts loam to 2 parts sand. The plants are well watered and allowed to dry before watering again. We have been fertilizing the plants on a monthly basis with a balanced fertilizer. The trees are hardy down to 20°F (-7°C). In the winter months, the plant are moved to the cool room where nighttime temperatures drop to 48°F (9°C). Plants are watered very little during this period and fertilizer is withheld.
Propagation: Phoenix dactylifera is best propagated from seed. Seed obtained from fresh dates will germinate in 14-21 days at 70°F (21°C).
Phoenix dactylifera was featured as Plant of the Week October 26-November 1, 2007.
Guide to Past Plants-of-the-Week:
Cal's Plant of the Week was provided as a service by the University of Oklahoma Department of Microbiology & Plant Biology and specifically the late Cal Lemke, who used to be OU's botany greenhouse grower and an avid gardener at home as well. If the above links don't work, then try the overview site. You may also like to look at the thumbnail index. ©1998-2017 All rights reserved.