43°F
weather icon Cloudy

Flower bloom determines pruning time

Question: I would like to cut back some cassia, Texas ranger and Rosemary plants that have grown too large. When is the best time to do so?

There are three cassias that are commonly planted here: feathery cassia, silver leaf cassia and desert cassia. They bloom either in the spring or spring and fall. The flowers have to be formed on last year's wood if they bloom in the spring. If you don't want the flowers, prune them back during winter months after leaf drop.

On those plants that are grown for their flowers, prune them as soon as their bloom time is over regardless of the time of year. If plants bloom in the spring, prune them as soon as they are done. This will give them time to initiate flower buds during the late summer for next spring's bloom. If they bloom in the summer months, they put flowers on spring growth , so you run the chance of pruning off all the flowers .

Bob Morris is a professor emeritus in horticulture with the University of Nevada and can be reached at extremehort@aol.com. Visit his blog at
xtremehorticulture.blogspot.com.

THE LATEST
Why did my bird of paradise plants quit blooming?

They were in bloom when we planted them five or six years ago, and they bloomed the following year as well. But they have not bloomed again.

What’s the best schedule for drip irrigation?

The correct amount of water to apply depends on the size of the plant and the number of days between irrigations.