Roses need help surviving winter months in zone 5. USDA zone 5 has annual minimum temperatures in the range of -10 to -20 degrees Fahrenheit and includes parts of Illinois, Iowa, Missouri and Pennsylvania. To help your roses through the winters in zone 5, start in the fall before any hard freezes occur. When you properly insulate the ground around your roses and protect them from disease and animals, you can enjoy their blooms each spring.
Stop feeding your roses in mid-August. If you continue feeding them, they will develop new growth late in the year that probably would not survive the winter.
Prune long rose canes in late August that might whip around in the wind during the winter and loosen the plant in the ground. All the canes on any particular plant should be approximately the same length. Spray the cuts in the canes with an anti-desiccant made for roses to prevent their drying out.
Rake and remove all the leaves and dead flowers after they have fallen from the roses. Do not use the fallen leaves and flowers as a mulch. A thorough cleaning of the rose patch will reduce the chance that spores from fungal diseases survive the winter near your plants.
Wait until the ground is completely frozen near the beginning of December. Spread 8 to 10 inches of organic mulch over each rose bush to keep the soil frozen. If there are alternate thawings and freezings, the roots can break and become damaged by freezing temperatures. Use pine needles, straw, bark or garden soil for the mulch.
Leave the mulch in place until there is no more danger of hard freezing, usually after late April. Removing the mulch earlier leaves the roses susceptible to cold snaps in the late spring.
Things You Will Need
- Pruning shears
- Organic mulch
- Think twice about using Styrofoam rose cone covers. If you do use them, tie the canes together with twine and deploy the cones only later in the year when the weather is quite cold. If there are very sunny days during the winter, they can heat up the roses inside. In this case you will have to open the cones to air out the roses.
- Roses planted in containers must be brought inside to a basement or storage shed for the winter.
- In places with extremely harsh winters, some rose growers tie each rose bush in a bundle using non-organic twine. They then dig a trench next to the roses and bend the plants into the trench and cover with the soil they removed to dig the trench. This is a good way to insulate the entire plant, not just the roots.