How to Protect Outdoor Roses From Freezing

Roses are incredibly beautiful but quite vulnerable to winter temperatures and frost. Proper protection and planning will ensure your roses survive the winter and thrive throughout another blooming season. Here are some tips to help you protect your roses throughout winter.

Roses are one of the most beloved flowers in the world that make a beautiful addition to any garden. With so many cultivars available, most gardeners can find a rose that captivates them. However, like other perennials, roses require a period of dormancy during the winter to rest and generate resources for the next blooming season.

It is important that these lovely flowers receive protection during the winter, as unusually cold or extreme weather can damage rose plants. While some hardy varieties may not require special care during a typical winter, other varieties are naturally more vulnerable to frost damage.

It is impossible to change the weather, but there are some steps you can take to protect your outdoor roses from being damaged when temperatures drop. This article presents a few ideas on how to keep your roses protected throughout the winter.

How Does Freezing Weather Affect Roses?

Most people consider freezing to be the condition where the air temperature is at 32˚F (0˚C), and that is true. However, plants don’t become damaged immediately upon coming into contact with freezing air. In most cases, plants are considered at risk for freezing when temperatures remain at 28˚F (-2˚C) or lower for more than four hours.

Of course, there will be variations as several factors play into how a given plant will react to freezing conditions. The species, how mature it is, and other environmental considerations all affect how a plant reacts to cold weather.

Roses can withstand short periods of below-freezing temperatures, but prolonged cold is dangerous. Temperature fluctuations are especially harmful to roses, as their cells experience the stress of thawing and refreezing multiple times. In addition, strong winds or accumulated ice can cause physical damage sufficient to kill roses in some cases.

Signs of Cold and Frost Damage in Roses

It may not be evident during the winter that a rose has suffered from frost damage, but once the plant enters its active growth stage, the symptoms become apparent. A frost-damaged rose may have some or all of the following problems:

Giving roses ideal care throughout the growing season will help them stay strong enough to survive the winter unscathed. However, there are several other steps you can take to maximize your roses’ chances of survival during a cold winter.

How to Protect Outdoor Roses From Freezing

1. Choose Roses Suited to Your Location

The majority of rose cultivars available grow in USDA hardiness zones 7 to 10. Certain varieties of roses can grow in zones 3 or higher. If you live in a climate with prolonged low temperatures, be sure to only plant rose cultivars that can withstand harsh conditions. Check labels or consult with garden center staff to ensure the rose you purchase is suitable for your climate.

Also, remember that your garden has various microclimates based on light, heat, wind, and water conditions. If frost damage is a concern, be sure to plant roses away from depressions or wet areas that stay colder than the rest of the garden.

2. Cover Your Roses

Covering roses during the winter months has several benefits. It not only protects the plant from high winds and ice damage but also keeps the plant at a constant temperature during the winter months and avoids temperature fluctuations.

Preparing to Cover Your Roses

Plan to cover roses once the temperature is below freezing for several nights, or after a hard frost causes the plant to lose most of its leaves. Roses should be bare-stemmed, with no remaining leaves or blooms. Tall canes can be pruned, as well as any damaged or dead stems, before covering them. Bundle and tie the canes to minimize them being blown around by the wind.

Don’t be shy about pruning roses. The goal is to cut them back to about one-third of their current size. This is the best way to prepare plants to produce new growth once the weather starts to warm. Make cuts at an angle, just above a bud, to encourage new stems from each bud.

Choosing an Insulating Material

There are many options when choosing a material to cover and protect roses during the winter. While there are pros and cons to each, many gardeners prefer not to invest extra money to insulate roses, so they use whatever is readily available.

Some potential options include:

There are a couple of considerations to keep in mind when choosing insulating material. First, if you decide to use old blankets and sheets for this purpose, they must be kept dry. Wet bedding will make your plants even colder, so use them in conjunction with plastic.

The plastic covering should not be allowed to come into direct contact with roses because cold can affect plants through the plastic barrier. Instead, use a frame around the plant to prevent contact with the covering.

An ideal scenario is a wood or metal frame around the plant, wrapped in a layer of old blankets or other fabric, and then a layer of plastic around that to keep everything dry.

3. Mulch Around the Base

Mound at least a foot (0.3 m) of soil or compost around the base of the rose plants. This helps regulate the temperature around the roots and lower stalks. Be sure to remove the layer of mulch once the weather warms up in spring, to avoid high temperature and moisture levels around the root system.

4. Keep Roses Thoroughly Watered Before the First Frost

Usually, there will be enough rain to keep the soil moist in the late fall. However, in especially dry years it is important to water roses when you know a freeze is predicted. This is important because moist soil holds heat much better than dry soil.

Treatment

Frost-damaged portions of rose plants can’t recover their health, so any unhealthy pieces should be pruned once the weather starts to get warmer. Be sure not to cut back roses too early, as that can further injure the plant. All danger of freezing should have passed before you attempt any pruning.

It can take a frost-damaged rose plant several seasons to fully recover, so it is better to prevent the damage from happening in the first place. By taking precautions early, you can maximize your roses’ health and be rewarded with plenty of blooms.