Oleanders In Containers Not Blooming

Q. I have two pink dwarf oleanders planted in 18 inch clay pots which are healthy looking but very few blossoms. One of my “expert” 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 some blossoms?

Oleander flowers

A. We have dwarf oleanders at the Research Center in containers and they bloom just fine. The usual reasons for a lack of flowering are not enough light and pruning them incorrectly. Oleanders use a lot of water when it’s present.

There might be a couple of things you could try. Oleanders should be in full sun. They love the heat, and they love water and fertilizer to perform their best.

If the container is smaller you might have to water more often. 18 inch containers are not that large and don’t contain a lot of soil. If the soil volume is not large, the plant may not have enough water in the soil to last between irrigations.

Oleanders that are not getting enough water will look normal but have a very open canopy and not bloom well. Containers are not very forgiving when it comes to water. The water in that soil can be used up fairly quickly.

You can try using a soil moisture meter that you can buy from the nursery for about $7 and check the soil moisture before you water. Water when the meter is about half way between wet and dry, do not let the soil go totally dry.

Next, use a fertilizer like Miracle Gro or Peters and water it into the soil about once every six to eight weeks. Oleanders growing in the ground do not need to be fertilized as often.

Next, 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 they will not produce any flowers or very few. Don't prune it with a hedge shears if you want flowers, contrary to how you see it done around town.