2007-04-28 / News

How to help freeze damaged plants, trees recover

SPRINGFIELD - Garden plants and some trees throughout Ohio may have suffered freeze damage from the recent cold snap, but steps can be taken to help plants bounce back to their lush and vibrant green selves.

A sudden drop in temperature, as low as 20 degrees Fahrenheit, followed a period of above-average 80-degree temperatures across Ohio. The change in weather set the stage for the potential for plant injury.

"Obvious signs of injury to flower petals were visible within a few days. Damage to foliage is still showing up and damage to branches, stems and woody tissue may not become evident until it gets warmer," said Pam Bennett, an Ohio State University Extension horticulturist in Clark County and the state coordinator for Extension's Master Gardener program. "The amount and significanceof the damage is species related, as well as to the particular growth and development stage of the plant when the freeze occurred. Species in some areas of the state experienced damage while others had none."

Individuals can take steps to help plants recover from damage as the spring season progresses:

+ For perennials, cut brown foliage back to the crown of the plant to encourage new growth.

+ Pruning is a good remedy for trees and shrubs that have suffered branch and stem damage. Trees and shrubs that have been damaged from the cold weather will turn brown around leaf edges and begin to defoliate.

+ Don't jump the gun on fertilizer. "Don't assume that twice as much is better, because it's not," said Bennett. "Despite the damage some plants may have received, continue regular fertilization practices."

+ Maintain good sanitation in and around garden beds. Letting dead leaves and plant material sit can cause a disease called Botrytis blight. "The disease is favored by cool, rainy spring and summer weather," said Bennett. "The disease spreads easily and will continue spreading until dry conditions return. Keeping wet debris away from plants will help manage the disease."

+ Be patient. "Watch and observe how plants perform as the season progresses," said Bennett. "Many plants, trees and shrubs may not show signs of freeze damage right away, and it could take some time for plants to recover."

+ Allow young, thin-branched trees that have suffered frost cracking to heal on their own. "Do not apply wound dressings. Allow the tree to close the wound naturally," said Bennett. "Frost crack can be a common problem and many trees are able to recover if the damage isn't severe."

Return to top