Published on 02/08/01

Plants Suffer, Too, From Summer Sunburn

Photo: Wayne McLaurin

Sunburned peppers like these can best be prevented by growing a healthy plant with lots of foliage to start with.
Those first hot days in the summer outdoors -- ah, remember the sunburn? Your garden plants may know the feeling.

"Long, sunny days and hot temperatures can lead to sunburn on some vegetable plants," says Wayne McLaurin, an Extension Service horticulturist with the University of Georgia College of Agricultural and Environmental Sciences.

One symptom of sunburn on fruit, he said, is large, white spots, particularly on the southern side of the plant. Most of the Solanaceae family -- tomatoes, peppers and eggplants -- are especially susceptible.

Prevention is the Key

When plants are sunburned, you can't rub a lotion on them and make them all better. The only way to help is to prevent it long before it could happen. And the only sure way to prevent sunburn on plants, McLaurin said, is to grow a strong plant with good leaf coverage.

This means growing or getting a good transplant, then planting it right, giving it the proper nutrition to help make sure the foliage provides ample cover for the fruits.

Leaves Vital for Growth

Leaves have an even more important function, he said. The plant's food for growth is manufactured in the leaf area.

There's a critical point, McLaurin said, at which the plant goes into a reproductive mode instead of a vegetative mode of growth. But if it hasn't made enough vegetative growth, it won't bear fruit as it should.

"In other words," he said, "you must grow a plant before you can expect fruit from it."

Photo: Wayne McLaurin

Sunburned tomatoes aren't a pretty sight.
Buy Bloomless Transplants

When you buy transplants, he said, don't buy any plant that has fruit or blooms. If you do, remove them before you plant.

Make sure your plants get enough water and fertilizer, too. That keeps them healthy and reduces stress.

"With a little care," McLaurin said, "you can prevent sunburn on your favorite plants and ensure proper growth and fruiting as well."

Dan Rahn is a news editor with the University of Georgia College of Agricultural and Environmental Sciences.