Pruning And The Care Of Knock Out Roses

Patricia M. Arledge, Sharpe, Kenneth W.

Knock Out Roses.jpg thumbnail

News Article for August 29, 2016:

In the midst of flood clean up I could see a Knock Out Rose starting a new bloom cycle. This particular plant had been covered with 4feet of water during the flood and it would have only had the very top of the plant out of water.

To me it shows the fury of nature along with the beauty and tenacity of plants.

Shrub roses, like Knock Out, tend to get bigger than the 4’x4’ that is normally predicted. With our long growing season and adequate rainfall they can mature at 8’x8’ if left unpruned.

Late August through early September is a good time to take off some of the excessive growth of rose plants. This time of the year I would take off no more than one-third of their foliage. That will allow you to shape up plants and give them some size reduction. If you need to take more off wait until late January and then you can take off up to two-thirds of the growth and get serious about taming plant size.

This late summer maintenance pruning will also help set you up for good fall flowering.

When it comes to the more traditional roses like hybrid tea types, you can cut canes back to about 30 inches from the ground. If you have weak plants that have put on very little growth during this growing season they should be pruned very little. Use a sharp pair of shears to make clean cuts. Also make your cuts to a bud on the outside of the canes so new growth will grow to the outside. If you cut to an interior bud the new growth will cross the interior of your plant and reduce airflow which favors diseases. Remove any dead or diseased tissue by cutting back to healthy wood.

Climbing roses should not be pruned now. Wait until after climbing roses bloom and then prune them. Older varieties such as Seven Sisters climbing roses will bloom in the late spring to early summer. If you pruned now you would cut all of the flower buds off and miss their floral display next year.

After you have finished pruning remove all weeds and freshen up your mulch. You can give the plants a light application of fertilizer to help with fall blooming but do not go heavy.

For more information on these or related topics contact Kenny at 225-686-3020 or visit our website at
9/14/2016 2:44:23 PM
Rate This Article:

Have a question or comment about the information on this page?

Innovate . Educate . Improve Lives

The LSU AgCenter and the LSU College of Agriculture