Plant Problem Diagnosis Key / Growing conditions
Growing conditions
Sunscald
Fruit suddenly exposed to strong sun overheats on the exposed side. It follows heavy pruning or leaf loss to disease or insects.
Signs
- A pale, papery, shiny patch on the side of the fruit facing the sun.
- Plants with few leaves over the fruit.
What favors it
Heavy pruning, leaf loss to disease or insects, and heat waves.
Prevention
- Prune lightly in hot regions; leave leaves over fruit.
- Cage rather than stake-and-prune tomatoes in hot climates.
- Control leaf diseases that strip the canopy.
Crops it shows up on
Tomato, pepper & eggplant; Apple, pear & stone fruit; Cucumber, squash & melon.
Often confused with
Sources
- Sunscald of VegetablesUniversity of Maryland Extension
- Sunscald on Vegetable LeavesUniversity of Maryland Extension
- Tomato disordersUniversity of Minnesota Extension
- Staking tomatoesChicago Botanic Garden
Treatment by crop
Cultural, biological and chemical options in the order to use them, and notes written for each crop.
Identification is free. Treatment is on the Home and Pro plans.
Questions in the key that lead here
- Look the plant over, leaf undersides included. Are insects, mites, slugs, eggs, webbing or droppings on it?
No, only damage or discoloration - Where is the problem?
Fruit, flowers or buds - What is wrong with the fruit or flowers?
Spots, patches or scabs on the skin - What do the marks look like?
Pale, papery patch on the side facing the sun
Not a match? Start the key or describe what you see.
More from university Extension: search Extension pages on sunscald, or find a plant diagnostic lab through your state's Extension.
Other growing conditions
- Blossom drop
- Blossom-end rot
- Cold and frost injury
- Construction and root damage
- Drought stress (underwatering)
- Edema (oedema)
- Fruit cracking
- Girdling roots and a buried root flare
- Heat and light stress
- Herbicide injury
- Leaf scorch and drought stress
- Light bleaching
- Mower, trimmer and animal injury
- Normal fall needle drop
- Not enough light (stretching)
- Overwatering (low root oxygen)
- Road salt injury
- Southwest injury (winter sunscald and frost cracks)
- Transplant shock
- Winter burn of evergreens