Protecting Roses for the Winter: Winterize Your Roses
Winter hardy roses are ideal for gardeners who love roses but do not want to provide much if any winter protection. Selecting roses that are appropriate for your hardiness zone is very important. Roses listed in our ‘Winter Hardy’ section meet that criteria and will provide the joy of having roses in the garden even under the most adverse conditions. All the roses we produce are on their own roots making them less vulnerable to winter injury. There are shrub roses, groundcovers and climbers from different breeders including Griffith Buck, David Austin and a few that were bred in Canada to withstand some very severe cold. You will find a size and color to meet any gardening need.
During his time at Iowa State University, Griffith Buck developed a group of roses that not only could withstand the Iowa cold by proved to be disease resistant. While other roses need protection in zone 5 the Buck roses do not, although some protection in zone 4 is advisable. In order for these roses to be ready to over-winter in zones 4 and 5 they should be planted by July 1st.
Winter protection is more than just covering the roses in the winter. A healthy rose is one that will be better able to withstand the cold and ward off disease, so to be successful you need to keep a few things in mind.
- Choose the right rose for your area keeping in mind that roses would like at least 5 hours of sun a day.
- Check the soil ph. It should be between 6 and 6.5.
- Make sure the soil has good drainage as that will help in root establishment.
- Fertilize regularly. Rose are heavy feeders and do not like to miss a meal.
- Water at ground level about 2” a week; more if the weather is extremely warm.
- Stop applying fertilizer in late summer. You want to slow down new growth as this will enable the plant to go dormant.
- Stop deadheading in the fall to allow the rose to form hips; this is a signal to the plant that it is time to start getting ready for winter.
If you elect to give the roses some winter protection you can get advice from your local rose society as to what is practiced in your area. You may find the American Rose Society website helpful at www.ars.org. Make sure before you start to winterize you clean up the ground and the bush as old debris and leaves will harbor pests and disease. Wait until spring to prune.
There are many ways to protect your roses for winter. One practice we use here at the nursery is ‘hilling’. You can pile or ‘hill’ up loose soil around the base of the plant. It should cover the center of the plant and form a mound at least 12” high and wide. Do not scrape the soil from around the plant for mounding as this could disturb the roots near the surface and may subject them to winter injury. You will need to bring in extra soil to ‘hill’ your roses. After you ‘hill’ them you can cover the soil mounds with mulch. Straw and then fir boughs or branches work well.
Another approach to winter protection is the use of Styrofoam rose cones. Be sure to follow directions carefully as they must be used properly to avoid damage. First, do not cover the plants too early. Follow the same timing guidelines as other methods. Second, the cones need to be well ventilated so heat does not build up on the inside during sunnier winter days. Cut four or five one-inch holes around the top and bottom of the cone to aid in ventilation and to keep the air inside the cone from heating up. Before placing the cone over the rose, mound soil up around the base of the rose. It you are trying to protect a more tender variety you can remove more off the top of the cone and fill the inside with straw. Place a weighted object on the cone to keep it from blowing away.
Climbers and larger shrub roses are more challenging to protect but it can be accomplished by bending or laying down the canes and covering with straw and dirt. Care needs to be taken so as not to damage or break the canes. If roses need to be left on pillars or structures, straw and burlap can be placed around the canes and the entire support wrapped and tied.
Keep in mind that your goal is to prevent the rose bush from freezing and thawing, so winter protect after you have had a couple of hard freezes. Protecting roses from the cold, severe windy months of winter is especially important. When spring and summer arrive and you experience the beauty of your roses you will be glad you made the extra effort and time.