Why Are My Tomato Plant Leaves Curling Up?
Rolled, curled tomato leaves come from heat, water stress, herbicide drift, pests or disease. Learn which curl pattern means what and when to act.
Updated September 27, 2026
Read the curl
Upward rolling of older leaves on a hot afternoon is usually physiological — the plant reducing its leaf surface to save water. If the leaves unroll in the evening and the plant otherwise grows fine, it is a response to heat, not a disease.
Downward curling on new growth, twisting stems, or rolling plus yellowing, spotting or wilting means something is actively wrong.
The causes that matter
- Heat and dry air — the most common and least dangerous. Mulch deeply, water consistently, and provide afternoon shade in extreme heat.
- Uneven watering — long dry-then-soaked cycles curl leaves and crack fruit. Mulch and a steady schedule fix it.
- Herbicide drift — if nearby lawns or fields were sprayed, distorted, twisted new growth with strap-like leaves is the signature. Severely exposed plants rarely recover; mildly affected ones may outgrow it.
- Broad mites and whiteflies — feed on new leaves, causing tight downward curl and stunting. Check leaf undersides; treat with insecticidal soap or neem and repeat weekly.
- Curly top or yellow leaf curl viruses — spread by insects, with thick, leathery, yellow curled leaves. Remove and destroy those plants to protect the rest — viruses do not have a cure.
When to worry
Curl alone, on an otherwise vigorous plant, almost never needs intervention. Curl plus discoloration, stunting, spots or wilting needs a closer look — take a clear photo of affected leaves from a few angles, since the pattern of the damage is what identifies the cause.
Prevention does most of the work: consistent deep watering, thick mulch, weekly undersides-of-leaves checks, and keeping weeds that host viruses and pests mowed down.
The pattern map: which leaves, which cause
- Older leaves, upward roll, worst in the hot afternoon hours, recovering overnight — physiological heat roll. No action needed beyond mulch and steady water.
- All leaves, tight downward curl, stunted new growth, fine stippling under the leaves — mites. Treat weekly with insecticidal soap and recheck the undersides.
- Only the new growth, twisted strap-like leaves — herbicide drift. Note spraying dates nearby; mildly affected plants often outgrow it, severe ones rarely do.
- A single plant declining fast with thick, leathery, yellow curled leaves while its neighbors stay fine — virus. Remove the plant immediately to save the row.
A prevention checklist for clean foliage
Mulch after the soil has warmed and keep 5 cm over the root zone all season, and water deeply on a steady schedule — a drip line or soaker hose beats overhead spraying, which both curls leaves in hot sun and spreads disease. Flip leaves once a week to check the undersides, because mites and whiteflies are only caught early by looking where they live.
Keep bed edges mowed and weeds down, since many weeds host the same viruses as tomatoes, and talk to neighbors before they spray herbicides in midsummer heat — 2,4-D vapor drifts on hot afternoons and twists tomato new growth far downwind. One calm-evening conversation prevents more curled leaves than any treatment.
How to fix curling tomato leaves
- 1Check whether older leaves roll upward on hot afternoons and unroll by evening — that is harmless heat stress and needs no treatment.
- 2Mulch deeply and water on a consistent schedule to prevent the dry-then-soaked cycles that curl leaves.
- 3Inspect new growth for twisted, strap-like leaves — the signature of herbicide drift from nearby lawn spraying.
- 4Check leaf undersides for broad mites and whiteflies, and treat with insecticidal soap or neem repeated weekly.
- 5Remove and destroy plants with thick, leathery, yellow curled leaves to stop the spread of curly top or yellow leaf curl virus.
Frequently asked questions
Should I remove curled tomato leaves?
Not for ordinary upward rolling — those leaves still feed the plant. Remove leaves only when they show disease symptoms like yellow spots, mold, or leathery thickening that suggests a virus, and dispose of them away from the garden, not on the compost pile.
Can curled tomato leaves recover?
Leaves rolled by heat or water stress often relax once conditions improve. Leaves deformed by herbicide or virus stay deformed — the test is the new growth, which comes in normal once the cause is handled.
Is leaf curl the same as tomato blight?
No. Blight shows as spreading dark or brown patches with a spreading dieback, while curl is a change in leaf shape. A plant can have both, but they need different responses — blight demands quick removal of affected tissue and often a fungicide.
Should I water tomatoes every day in a heat wave?
Deeply every 2 to 3 days beats a shallow daily sprinkle. Daily light watering grows shallow roots that panic in heat; a soak that wets the top 20 cm pushes roots down and keeps leaf roll at bay. Containers are the exception — they can need daily water in extreme heat, and mulch on top cuts that need roughly in half.