Winter injury showing in Kansas roses this spring

Late-season freezes damaged early rose growth, but proper pruning and care can help plants recover

Many roses across Kansas are showing signs of winter injury this spring, leaving gardeners with discolored canes, dead branches and delayed growth.

While roses are sensitive to extreme cold, this year’s damage is largely the result of fluctuating temperatures early in the season. Warm weather in February and early March encouraged early growth, which was then damaged by subsequent freezes.

“New growth in roses is very sensitive to cold temperatures,” said Matthew McKernan, Kansas State University Extension horticulture expert.

When tender new growth is exposed to freezing conditions, damage can occur quickly. Leaves may wilt and turn brown, while stems can darken — sometimes turning black — as internal tissues are injured.

What Damage Looks Like

In many cases, winter injury appears as dead or brittle canes, discolored stems or leaf drop. Severe injury may result in dieback several inches down the stem, and in extreme cases, entire plants may be lost.

However, most roses are expected to recover with proper care and patience.

Gardeners are encouraged to resist the urge to prune too early. Waiting until the threat of additional freezes has passed reduces the risk of further cold-related dieback and allows the full extent of damage to become visible.

“Delay pruning until the danger of hard frosts and freezes has passed,” McKernan said.

Once new growth begins to emerge, gardeners can begin pruning back damaged rose canes. Cuts should be made just above healthy growth, typically about one-quarter inch above a bud, at a 45-degree angle.

“Whenever possible, prune back to new growth that naturally points outward, away from the center of the rose bush,” he said.

Looking Ahead

While winter injury may set roses back early in the growing season, most plants will rebound with proper care. Taking time to assess damage and respond appropriately can help ensure healthy growth moving forward.

Avoiding early spring pruning in future years can also help minimize damage.

“Early season pruning induces rapid cane growth that will be susceptible to spring freezes,” McKernan said.

For roses grown in Kansas, it is best to prune after the threat of frost has passed and as new growth appears, with most of the state typically in the mid-April range.

McKernan adds: “Water roses deeply to reduce drought stress on the plant and aid in recovery. Proper fertilization at planting and during the growing season can also help boost growth.”

More information on the proper care of roses is available online from the K-State Horticulture Newsletter, or from local K-State Extension offices in Kansas.

PHOTO: Rose bush with fresh and withered flowers. (iStock-#1166477294 │ photographer)