Plant Problem Diagnostic
Sunscald on Tomatoes and Peppers
The short answer
Sunscald is sun damage, not a disease: when a tomato or pepper suddenly loses the leaf cover shading it and the fruit is exposed to intense direct sun and heat, the exposed side develops a pale, whitish, leathery, then dry and papery patch. It typically follows heavy pruning, defoliation from disease, or a sudden heat wave.
Because the cause is exposure, the fix is cover: keep enough healthy foliage over the fruit, avoid over-pruning in hot weather, and use shade cloth during extreme heat. Damaged fruit won't heal, but the plant will keep setting new fruit once it's protected.
How to recognize it
Look for a pale, bleached, white-to-yellowish patch on the side of the fruit that faces the sun. The tissue turns dry, leathery, and papery, and can crack or become a site for secondary rot.
It's noninfectious — it won't spread plant to plant like a disease — and it's most common during extreme heat when fruit is suddenly exposed.
Preventing it
Maintain leaf cover over developing fruit for as long as possible, and resist stripping foliage in hot weather — over-pruning to 'improve airflow' is a common way gardeners cause sunscald.
During heat waves, drape shade cloth over the plants to shield exposed fruit. If disease has already thinned the canopy, supplemental shade cloth stands in for the missing leaves.
Sources
Reviewed 2026-07-18. We cite university Extension, government, and established horticultural sources — and never invent pesticide rates or dangerous treatments.
- University of Illinois Extension IPM — Sunscald of Pepper and Tomato — Sunscald is a noninfectious disorder caused by sudden exposure of fruit to intense direct sun during extreme heat; affected tissue turns white/papery; maintaining foliage cover prevents it.
- University of Minnesota Extension — Growing tomatoes (sunscald) — Sunscald appears as pale, papery patches on sun-exposed fruit, often after foliage loss; adequate leaf cover and avoiding over-pruning prevent it.