A general answer ( since you did not specify what plant ) is insect damage, drought, or soil is too alkaline.
Sunlight causes this.
New leaf growth is caused by the cold soil causing the leaf to curl and fall off producing a new leaf. The cause of the leaf to curl can be from an aphid species or different plant diseases.
stunted plants leaf curl up as a cup shape hard leaf midrib yellow leaves
Leaf curl on bitter gourd plants can be caused by various factors such as viral infections (e.g., cucumber mosaic virus), excessive heat or sunlight, herbicide damage, or certain pests like aphids and whiteflies. Proper monitoring and prompt treatment of the underlying cause can help manage leaf curl in bitter gourd plants.
Feeding, for instance aphids; leaf hoppers and rollers, and psyllids. Fungus, for instance nectarines and peaches. Spraying, for instance 2, 4 D drift; or Banvel or Roundup control reactions. Overwatering, for instance tomatoes. Viral, for instance mosaic virus; or squash or tomato yellow leaf curl virus.
To prevent or treat leaf curl on tomatoes in your garden, you can ensure proper watering, provide adequate sunlight, and avoid over-fertilizing. Additionally, you can use fungicides labeled for tomato leaf curl if the problem persists.
To prevent or treat leaf curl in pepper plants, ensure they have consistent watering, proper drainage, and adequate sunlight. Avoid over-fertilizing and protect plants from extreme temperatures. If leaf curl persists, consider using a fungicide or insecticide as directed.
Lemon leaf curl can be caused by factors such as pests like aphids and spider mites, fungal infections like citrus leaf miner, or environmental stressors like overwatering, under fertilization, or extreme temperatures. Proper pest management, maintaining good air circulation, and providing appropriate care can help prevent lemon leaf curl.
Stink bugs
The tomato leaf curl virus is a yellowing and upward curling of leaves on a tomato plant. It is a viral infection that has been transmitted through whiteflies. It will affect fruit production.
To prevent or treat leaf curl in tomato seedlings, ensure they are planted in well-draining soil, receive adequate sunlight, and are watered evenly. Avoid over-fertilizing and maintain consistent temperatures. If leaf curl persists, consider using a fungicide or contacting a local gardening expert for further advice.
soil