Nerium oleander, or Oleander, is an evergreen shrub native from the Mediterranean area to Southeast Asia. It is also one of the most poisonous shrubs known today. Shrubs if left untrimmed can reach up to 20 feet (6 m) tall with a spread of 10 feet (3 m). The leaves are 4-10 inches (10-25 cm) long and are in whorls of 3. We received a cutting from a plant in the Phoenix area several years ago. Since they are native to mild climates they are considered a basic shrub for desert gardening. In colder climates they make an outstanding container plant. They are very easy to grow and very drought resistant and not particular about soil conditions. Plants are hardy in USDA zones 8-10. All plant parts are poisonous and should not be planted where children and pets play.
Blooming: Oleanders bloom in spring in the greenhouse. Ours has a pure white flower with a pale yellow center.
Culture: Nerium oleander needs full sun to very light shade with a well drained soil mix in containers. In the greenhouse, we use a soil mix consisting of 1 part peat moss to 2 parts loam and sand. The plants are well watered and allowed to dry completely before watering again. Plants in containers do better with regular watering and supplemental fertilization. We fertilize our plant monthly with a balanced fertilizer diluted to 1/2 the strength recommended on the label. Plants should be rested in the winter months in containers and very little water is used during the period. We keep our in the cool rooms where nighttime temperatures are 48°F (9°C) at night. During this period, plants are watered only enough to keep the leaves from dropping and fertilizer is withheld. Plants in the landscape or in containers should be pruned in the spring to shape and control their size.
Propagation: Nerium oleander is propagated from cutting and from seed when available.
Nerium oleander was featured as Plant of the Week April 24-30, 2009.
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. ©1998-2012 All rights reserved.