6:30am

Sat October 27, 2012
Garden Report

Winterize Your Garden

As colder weather and winter approach it’s almost time to start winterizing your roses. KUNC Gardener Tom Throgmorton offers tips on how to insure your roses make it through to spring.

Grafted roses grown in the Rocky Mountain region need protection. Temperature extremes from below zero degrees one week and 65 degrees the next week take their toll. Desiccating winds suck the moisture out of exposed canes. Just a little insulation keeps roses alive.

Roses go dormant on their own schedule. It usually takes some hard freezes for them to lose their leaves. Insulating roses too early causes problems. The mulch is a natural nesting place for little critters. Once they’ve nestled into the mulch the rose becomes their prime winter food source. After a few hard freezes the rodents have found other living quarters and the roses are entering dormancy.

The rose graft is the most important plant area to protect. This is the bulge at the crown where the special named rose variety is attached to a hardy rootstock. At a minimum, cover the graft with 4 inches of mulch, soil or compost. Prune long canes to 24 inches above the ground.

Grafted, climbing roses offer a challenge. Some are definitely hardier than others. Research each variety on the internet or at your local garden center. If unsure or growing a less hardy variety, the entire cane needs protection. Un-trellis the canes and lay them in a garden bed. This is a thorny job. Cover the canes with at least 4 inches of mulch. The live canes can be re-trellised in early spring.

Some grafted roses tolerate winter extremes better than others. But without a lot of research and experience killing roses, it’s difficult to determine which roses are hardiest. Generally shrubby floribunda roses need some protection. Most hybrid tea and grandiflora roses benefit from winter protection. Winter insulation doesn’t hurt any roses.

Roses on their own root are another solution. These varieties have no graft union that can be damaged. The worst case scenario is, in a hard winter, the rose is killed to the ground. The hardy root will re-grow in the spring with the same flowering plant you started with.

Many own root roses have been bred in Canada. These plants are selected for their disease resistance, flower color, fragrance and ability to survive the harsh Canadian winters. Own root roses don’t need a bunch of extra care. They can be treated like any other shrub in the garden but they have rose flowers.

tom@throgmortonplantmanagement.com

Tom Throgmorton Garden Report 10/27