Herself's Houston Garden

Conservation through cultivation


If you are looking for a screening shrub that grows really fast you want an oleander. Flower come in pink or white varieties. There are small versions of oleanders as well that will not take over the place.

Oleander grows well along the coast, the edges of forests and in home gardens. It grows from between 3′ and 30′ tall. Flowering occurs through out the warm season. Plant in full sun for best flowering.

While it can withstand cool temperatures, ice is a threat, as are several extended freezes. Only the older established Oleanders survived last winter’s cold. Oleanders bend easily under the weight of water and ice and must be protected from breaking. The oleander grows so quickly though you could also just trim back broken branches once the weather breaks.

Once established they are drought tolerant but need regular watering the first year while they settle in.

Pruning is not necessary, but oleander will flower better if pruned. Remove suckers and prune after flowering is done for the year. Severe pruning will hurt flowering. Remove suckers, dead branches, branches that have over grown other branches and just lightly to keep the shape of the plant nice.

Oleanders have Cardenolide Glycosides in the sap. It can cause death in sufficient quantities. It is very bitter tasting and nauseating so it is unlikely you’ll be eating much of it. Fumes from burning oleanders are also toxic. Because it is so common it is a favorite plant of poisoners and suicides.  So toxic is it, that like rhododendron, honey made from the flowers may be toxic as well.  Do not toss oleander cuttings in the compost pile, it can remain toxic even in the compost for almost a year.

Oleanders are believed to be native to the Mediterranean and were transported to warm regions around the world from there by early traders in the early 1800s.

Oleanders should be pruned in the early spring, around Valentine’s Day is a good time. This way you don’t have to cut off flowers or buds. However you can prune oleander any time of year. Since the milky white sap is poison, be sure to wear gloves and keep your fingers away from your face while pruning. The sap also irritates some people’s skin. Dispose of cuttings where children and pets will not get into them.

You can lightly prune them to keep them from looking scraggly, or you can prune them into a tree shape by removing lower branches. Cutting the stems encourages branching so cut the stems to about half the height you’d like to allow for branching. You can also prune oleander to the ground if it gets totally out of hand. It will come back bushier.

Watch for leaf scorch both bacterial ( see comments below ) and from dry windy conditions.  The leaf scorch from windy, dry weather can be treated by watering more frequently and deeply.

Aphids can be a problem, treat with soapy water or orange oil.  They may cause black sooty mold to grow on your plant. The black soot can be washed off with soapy water.

Scale and caterpillars will also attack oleander.  Treat scale with orange oil.  Caterpillars I’m not sure of a good treatment.

That  said I’ve had not a single problem with any of my oleanders until the cold winter of 2009-2010. All of my miniature oleanders died. Many of my neighbors large oleanders are heavily damaged but look like they will come back once the weather warms. Just remove frost damaged branches and they should be fine.

Stay away from the dwarf oleanders they are not drought or cold tolerant and prone to scale.

More information:
International Oleander Society
Oleanders for Florida