The Oleander Tree - Pretty Poison
The oleander tree, Nerium oleander, is an attractive plant, easy to grow and care for. In its natural state, oleander will grow as a large shrub but can easily be trained to grow as a hedge, a screen, or as a small tree.
The oleander tree is rather quick growing and it takes a certain amount of pruning to shape it correctly and to get multiple trunks to grow more or less as a single trunk. If not pruned properly, the branches can at times be weak, especially at the crotch, and may break off in windy conditions. A row of trees can make an attractive screen, or dwarf varieties of the plant can be used as landscaping borders in residential areas. The oleander tree is an evergreen, and in some locations it will flower most of the year. In other locations it may flower to a lesser extent or not at all during the winter months. Growing oleander is generally restricted to USDA zones 9 and up. It is not hardy in other zones, and can easily suffer damage during cold winters. It is not a large tree, sometimes growing to not more than 10' tall, but can grow as high as 18'. It has a spread of up to 15', so if properly pruned and trained can become a very handsome specimen.
Red Flag Warning! - If you are thinking of planting an oleander tree or shrub on your property, be aware that the oleander is poisonous, very poisonous in fact. All parts of the plant are highly toxic, and just nibbling on a twig could make someone very ill indeed. Oleander should probably not be planted where small children might decide to sample a leaf, not should it be planted where livestock could get at it. An oleander shrub or tree is one of the more dangerous plants to have if one keeps horses where they might be able to reach the leaves.
Only The Caterpillar Is A Threat - The oleander tree is something of a tough customer in the zones where it can be grown. It is extremely drought tolerant, and once established seems to be at home even in powdery dry soil. It is also not terribly choosy about the type of soil it is planted in. Oleander trees and shrubs will be found growing in hard compacted soil, soil with poor drainage, and in areas where air pollution may be particularly bad. Even though the plant produces seed pods, wildlife generally ignores it. The main enemy of the oleander tree appears to be the oleander caterpillar, which in sufficient numbers can strip a tree of its foliage in a relatively short time.
Many Cultivars, Many Colors - The color of the tree’s flowers depends upon the cultivar chosen and may be red, pink, orange, yellow, or white. Most blossoms have a pleasant fragrance. One of the more hardy cultivars is "Calypso", which features red blossoms. Another red flowering oleander tree is "Barthelemy", which has double blossoms. "Sister Agnes" and "Isle of Capri" have white and yellow blossoms, respectively. While most oleanders have flowers of a single color, the cultivar "Hawaii" has blossoms which are salmon pink with a yellow interior.
If you are growing your own oleander tree, you'll find it quite easy to care for. A yearly application of fertilizer will be beneficial, at least for the first year or two, but an application every year is even better. As mentioned before, pruning is required to get the best and strongest shape. The oleander will often grow suckers from the base, and these should be cut away as they appear. If allowed to grow, you'll end up with many suckers and fewer flowers, as the suckers tend to take up too much of the plant's energy. Cared for properly, the leader tree will be a very valuable asset to anyone's landscaping scheme. It cannot be stressed too much however, the dangers the plant carries with it in being so highly poisonous.