What causes my citrus tree's new leaves to curl up?
Citrus Leaf Curl
Certified GKH Gardening Expert
Leaf curl in citrus can be caused by several cultural and pest and disease problems. Under-watering AND over-watering can bring about ‘leaf curl’, so you need to check soil conditions first. Is it too wet or too dry? Wind injury can cause crinkling and curling. Is your plant situated in a location exposed to strong winds? If so,move it to a sheltered location.
Leaf miner is a very common citrus insec tproblem, causing the leaves to distort and curl. It is easily identified - edges curled and a pale green track or whitish lines running over the surface of the leaf. If the leaf miner is your problem, cut off the affected areas. Aphids,thrips and scale can cause leaf curl as well. Do you see an infestation of tiny little insects on the young leaves, or funny looking ‘bumps’ on the mature leaves? If so, one of these could be the culprit and should be treated accordingly. Fungal problems cause leaves to curl, particularly powdery mildew and scab. Powdery mildew can be identified by a white powdery substance on the surface of the leaves. Scab can be identified by the presence of patches of raised ‘rough tissue’ on both the leaves and the fruit. Neem oil can help with both insect and fungal problems. Here is more info: https://www.gardeningknowhow.com/plant-problems/pests/pesticides/neem-oil-uses.htm