Knock Out® Rose Winter Care
I have a beautiful Knock Out® rose that I had just planted this past spring. I'm not too sure on when to cut it back for winter. The web says not to prune until spring. Is that true? And to just cover the base with mulch to help protect it for winter? What am I to do? Please help!!!!!! Thank you.
Knock Out® Roses were developed to be exceptionally easy to care for and that includes winterizing. Knock Out® Roses are cold hardy to zone 5a, where winter temperatures can dip down to –10 to –15 degrees F.
In zones 5 through 11 you don't need to take any extra steps to care for your Knock Out® roses in winter. After the ground freezes a thick layer of mulch around the base, but not up against the canes, will keep the ground temperature even and prevent the roots from heaving. This happens when the ground goes through multiple freezes and thaws.
In climates colder than zone 5, gardeners will need to protect their Knock Out® roses. This should be done after the first hard freeze and before the first snowfall. The first step is to loosely tie the canes together to keep them from whipping around in the wind. Then cover the base of the plant with 12 inches of soil. Straw or leaves can be placed over the soil mound for additional insulation.
If you prefer to use styrofoam rose cones, prune the bushes back so the cone will fit over the plant. Before you cover the bush, mound several inches of soil around the base of the canes then place the cone over the rose. To keep the cone in place, mound soil around the outer base.
Depending on spring weather conditions, remove protective materials before the buds break open, normally in late March to mid-April.
Prune your Knock Out® roses in late winter or early spring, while the plant is still dormant. Remove any dead or damaged wood, do a little shaping if necessary, and take out some of the interior stems to improve air circulation. Every 2 or 3 years remove about one third of the old branches to stimulate new, fresh growth. If you are trying to keep the roses at a certain height, you can cut them back hard with hedge shears. No need to worry about usual rose pruning rule of cutting back to an outward facing leaf bud - just lop them down to the desired size. I've even seen Knock Out® Roses spring back beautifully after being cut down to 6-inches.