Symptom
Curling leaves
Leaves curl to save water in heat and drought, pucker around feeding insects, and twist when growth is disturbed by viruses or weedkiller. Look underneath and at the newest growth.
Turn the leaves over first. Insects under curled leaves settle it; if there are none, think about heat, water and anything sprayed nearby.
Likely causes
Ordered from the usual answer to the less likely one. Each links to the full problem.
Recorded on Tomatoes
-
Pest Common
Aphids
New leaves puckered around colonies of small insects. -
Light & temperature Common
Heat stress
Tomato leaves rolling upward in hot weather; plant otherwise fine. -
Damage Possible
Weedkiller damage
New growth twisted, cupped or fern-like. -
Viral disease Less likely
Cucumber mosaic virus
Curled, mottled leaves on scattered plants. -
Viral disease Less likely
Tomato mosaic virus
Distorted, mottled tomato and pepper leaves.
Less likely on Tomatoes