It is often possible to save a plant exhibiting signs of stress like curling and shaking leaves, but early intervention is crucial. By diagnosing the issue accurately and implementing the appropriate corrective measures, many plants can recover.
Leaf curl disease shows up in spring, does the damage, and then disappears (until next spring). If your trees were infected last spring, they should have completely recovered by mid to late summer. They usually grow lots of healthy new leaves (like the photo below).
Curled leaves are due to a light problem
Unaccustomed to these new growing conditions, your plant will fold up its leaves to limit its exposure to the sun. Move the pot to the shade and gradually get your plant used to life outdoors. Start by taking it outside for a few hours in the morning or evening.
Treat trees with a fungicide in late fall and winter. The fungal spores that cause the disease spend the winter on twigs and buds and germinate in the spring. For effective control, treat trees just after leaves have fallen, usually late November or December.
Leaves that curl or droop downwards often indicate overwatering or problems with the roots. Allow the soil to dry out further between waterings. Check for root rot and repot in fresh soil if needed. Keep plants away from cold drafts which can also cause downward curling.
Leaf curl can usually be controlled satisfactorily by a spray of a suitable registered fungicide at any stage of dormancy. Most effective control is achieved by spraying when the buds are swelling but before they have opened. It's not possible to control the fungus once it's entered the leaf.
Leaf curl starts appearing in early spring on stone fruit trees. Spray a mixture of apple cider vinegar and water in winter and early spring when buds appear, then every couple of weeks. This will help with brown rot, black spot and leaf curl, to name a few.
Managing Peach Leaf Curl. If you see symptoms of peach leaf curl in the spring, it is too late to treat the tree. Cutting affected branches or diseased leaves does not control the disease and can damage your trees. However, integrated pest management (IPM) will control the disease.
Curled leaves can be due to drought, cold damage, excess sunlight, sap-sucking insects or caterpillars that bind leaves. Control: See our advice in weather damage for further information on protecting plants from weather. Provide protection from stress and control insect pests to prevent curling.
Leaf Curl, prevention is the only way to deal with it that I know of. I start spraying my trees with Neem oil / Bonide Copper Fungicide mixture when dormant 3 times last spray when the buds start swelling but are still gray colored. Blossom Blight is a problem too, this spray takes care of that too.
During spring and summer in Southern California, she suggests drip watering three times a week for 18 minutes, then adjusting from there if the soil is too wet or dry. Don't know how to tell? Stick your finger in the soil. If it's consistently moist 2 inches down, your plants are fine.
Fungicide hints …
Spray your trees twice, the first time in late November and the second time in early February. A handy trick for remembering those dates is to spray right after Thanksgiving and just before Valentine's Day. Spray trees until they are dripping.
The fungus causes the growing cells at the leaf margins to multiply quickly and randomly which results in the curled and distorted appearance. The fungus then wastes no time producing spores on the surface of the leaf that spread to other leaves and fruits on your tree or other trees in the area.
“Move the plant out of direct sunlight or intense heat and be sure to mist the leaves regularly to stop this from happening.”
Prevent Leaf Curling
Another sign of magnesium deficiency, this problem can also be tackled with the help of Epsom Salt. Mix two table spoons in a gallon of water and spray your curled foliage with the solution until the leaves look perfect again.
Spray Nectarines, Peaches, Plums, Almonds with Yates Liquid Copper Fungicide Concentrate in late winter when buds just start to swell. Where leaf curl is likely to be a severe problem based on previous experience, spray first in autumn at leaf fall and then at the first sign of bud swell and repeat one week later.
Tree to tree spread of the pathogen occurs by airborne ascospores that can move longer distances or by blastospores, which are disseminated in splashing water. Leaves and the occasional fruit infections occur only on young plant tissue.
Over-watering.
Overdoing your watering can have a similar effect to underwatering. You may also find your plants produce an excess of foliage but few tomatoes. Leaves might yellow and wither, or they could curl.
Controlling the Spread of Peach Leaf Curl
Manually removing the infected leaves from the tree can help control the spread of Peach Leaf Curl. The discarded leaves contain fungus spores that can overwinter in the soil beneath the tree and reactivate in the spring.
It is often possible to save a plant exhibiting signs of stress like curling and shaking leaves, but early intervention is crucial. By diagnosing the issue accurately and implementing the appropriate corrective measures, many plants can recover.