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.