Protecting Roses from Winter
For gardeners in cold climates (USDA zones 6 and colder), hybrid tea and floribunda roses can be harmed by winter's cold. The cold winds and temperatures can cause the canes to die back to the ground. Most hybrid roses have been grafted. The graft union is where the variety you're growing has been grafted onto a rootstock variety with strong vigor or hardiness. If the union dies the rose that grows up from the ground in spring will be the rootstock variety and not the variety you planted. So, it's important to protect the graft union. For most heirloom, landscape, or own-root roses, you don't have to worry about this. They are either very hardy, or the roots are the same variety as the shoots, so if they die back the rose that sprouts will be the one you want.
To protect your roses, you'll need to cover them. You can buy rose cones and place them over the rose canes, but a cheaper and easier method is to bury the rose graft unions with bark mulch or straw. Shredded bark mulch or straw is coarse enough to let air freely circulate around the rose canes so they don't rot in winter. However, it still protects the canes from cold winds and fluctuating winter temperatures. Pile on a 1- to 2-foot deep mound of bark mulch over each plant or create a wire cylinder filled with straw. Don't worry about the canes that are sticking out of the mulch. They can be pruned in spring. Wait until early December to apply the mulch. By then most mice and voles will have found other places to spend the winter. If you mulch too soon, they will take up winter residence in your mulch pile and potentially gnaw at the rose canes all winter.
In spring remove the mulch at the first sign of the rose buds swelling. Prune back your hybrid roses to the 3 to 5 strongest canes and remove any canes that are winter injured.
Comments