The Proper Way to Prune and Hedge Oleanders

Formal oleander hedge, no flowers

Q. Would you please comment on the proper method and timing to prune and hedge oleanders.  This is two questions.

A. There are two types of hedges; formal and informal. You have to make up your mind which kind you want. Formal hedges are pruned with a hedge shears while informal hedges are pruned with a loppers or even a pruning saw.

Formal hedges are supposed to be pruned so that the bottom is wider than the top but they are maintained in a tight boxy shape. To maintain them properly, formal hedges need to be pruned two to three times during the growing season to keep the new growth restrained and maintain that boxy shape.

Oleanders flower on current season or summer wood

            Informal hedges can be pruned every two to three years, most of the pruning is done at or near the soil level and is done during the winter months. Formal hedges are best done on nonflowering plants that have small leaves. Informal hedges are best served by other types of plants, particularly those that flower during the summer.

You can prune any plant used for hedging in any manner you want but there are some big advantages in picking the right type of hedge for the right plant.

            Oleanders flower on new wood. In other woods after the winter rest its new growth supports the flower throughout the summer. Formal hedges, since they are pruned to maintain that boxy look, are pruned during the time of year when it is growing. If it wasn’t pruned then, in a few short months it would no longer be in that boxy shape. The problem you can see right away is that in picking a formal hedge for oleander you will prune off most of the wood that supports flowering so it will be pretty much a green hedge.

Shubs in this streetscape are "hedged" for no apparent
reason other than creating more income

            If you want to enjoy the flowers then convert it to an informal hedge. The problem is that 95% of the maintenance companies DON’T KNOW HOW TO PRUNE FOR AN INFORMAL HEDGE.  And it is very simple, there is far less mess, the cleanup time is very short but you ONLY HAVE TO DO THIS EVERY TWO TO THREE YEARS.  Now if I were a maintenance company, which type of hedging would I like to charge for. Hmmmm…. Once every two to three years or two or three times a year….

            Now if I really want to do a lot of work then why not make ALL the plants in a landscape boxes! That way I would have to prune them several times a year rather than once every two to three years! If I can’t make money mowing a lawn any more then lets charge for making all the plants in a yard into boxes… or gumdrops.

            Pruning for an informal hedge is quite simple. During the winter, once every two to three years, remove one third of the plant at or near the soil level. Pick 1/3 or ¼ of the largest stems and cut them off. This will only work on shrubs that have lots of stems coming from the ground. On plants which have a single stem or only two or three coming from the ground then you have to move this technique higher in the plant and inside the canopy.