Q. You had an article awhile back about trimming oleander down before spring. I have five in my backyard and have never done that. I am afraid to trim them down. Let me know because I am ready to fertilize.
A. If oleanders are getting old and unsightly you have two choices if you want to improve their locks. You can cut them down to the ground leaving stubs about 3 to 4 inches above the soil and they will sucker and regrow from these stubs.
This eliminates flowers early in the season but it will start flowering probably around July when it gets old enough. You can cut them back now. They grow back very quickly when it’s warm and they have plenty of water.
The second option cuts back a few of the oldest and largest stems in the same way but leaves the smaller ones unpruned or only cut back with some of the foliage remaining. The advantage of the second way is that you don’t leave and open space and the remaining smaller stems will flower much earlier.
Pruning them with a hedge shears in the spring and summer removes the future flowers and you’re faced with a green plant until it regrows and flowers.
Fertilize them and water them after they are pruned. This is important if you want them to grow back quickly.
Here are some places on my blog to check out http://xtremehorticulture.blogspot.com/2012/07/proper-way-to-prune-and-hedge-oleanders.html