Q. I have two pink dwarf oleanders planted in 18 inch clay pots which have very healthy looking foliage but very few blossoms. One of my "expert" gardener friends says simply that "oleanders don't like pots". Another "expert" says that I'm watering too much. Are either of these guys right or do you have any suggestions that might get some me some blossoms?
A. We have dwarf oleanders at the Research Center in containers and they bloom just fine. Thge dwarf oleander might be a better selection for containers. There might be a couple of things you could try. If the container is small you might have to water more often to compensate for the small soil volume.
Plants in containers need to be repotted every two or three years. Very small containers, every year. Large containers might make it up to five years.
Oleanders that are not getting enough water will look normal but have a very open canopy and not bloom well. Oleanders are high water users and love fertilizer. They do not like to be watered daily but will not do their best if the soil starts drying too much between waterings.
You can try using a soil moisture meter sold for houseplants that you can buy from the nursery for about $7. Water when the dial is about half way between wet and dry, do not let it get totally dry. Next, use a fertilizer like Miracle Gro and water it into the soil about once every six to eight weeks.
Cover the soil in the container with mulch to help keep the soil moist. About three inches would be enough. If oleanders are young, or if they are pruned with a hedge shears, flowers will be delayed or produce very few.
Don't prune with a hedge shears if possible. They should be pruned with pruning shears but not hedged or gimbaled.