By Susan Patterson, Master Gardener
Oleanders (Nerium oleander) are beautiful mounded shrubs with glossy leather-like evergreen foliage and brilliant blooms. Dwarf varieties reach 3 to 5 feet at maturity while full-size shrubs will grow up to 12 feet tall and 12 feet wide.
Pruning oleander shrubs is not necessary for health but will keep the shrub tidy and control growth. The time to prune oleanders and how to prune an oleander for best results are important considerations whenever oleander trimming does become necessary.
When to Prune Oleanders
To ensure the vitality of your oleander, prune at the appropriate time. Because they have a very short bloom time, the best time to trim oleanders is right after they bloom. For varieties that bloom well into the fall, it is imperative to have them trimmed by mid September.
Having the right tools makes pruning oleander shrubs easier. Hand pruners and loppers are usually sufficient to trim oleanders. Make sure that your tools are in good working order and sharp. Wipe all debris from your tools using a clean rag, soak them in a solution of one part bleach and three parts water for five minutes, and then rinse with clean water. This will help reduce the spread of pathogens.
How to Prune an Oleander
Oleander trimming is not difficult but requires some planning. Step back from your bush and formulate a pruning plan in your head. Take note of the desired shape you wish to achieve and get an idea of how much you need to trim away.
Annual pruning of oleander bushes involves inspection for dead or damaged limbs first. Remove these limbs at the ground or at the point where they join a healthy limb. As a rule, do not remove more than 1/3 of the entire bush. Trim branches just above a leaf node. This will encourage new growth.
Continual pruning in this manner will encourage your oleander to be bushy, rather than tall and lanky. Every two or three years you can prune your oleander for renewal. This means taking more than 1/3 off and cutting the oleander back aggressively.
Rake up and dispose of all debris after you have finished pruning.