Once leaf scorch has occurred, there is no cure.
What can you do? Once leaf scorch has occurred, there is no cure. The leaves that have already turned brown will not recover, BUT as long as you water properly, the rest of the plant should survive. Deep watering is recommended – a slow, deep soaking of the soil at the roots.
MANAGEMENT Leaf scorch is irreversible; however, proper water management may help the plant recover. To prevent scorch, water more deeply and less often to ensure that the water is deeply penetrating the soil, for deep root development.
The good news is that yes, your plant can recover from sunburn if it's not too bad. The bad news is that the sunburnt parts of the plant will never go away; it'll always have a scar if it does pull through.
Scorch damage alone is insufficient to kill an otherwise healthy plant. Proper treatment depends upon the reason for scorch symptoms; however, good cultural practices that improve general plant health and promote good root growth will reduce the chances of leaf scorch.
The tree will normally heal itself. Young, thin bark trees are most susceptible, particularly newly planted trees. Older trees of the same species develop thicker bark and established root systems. These species are at risk: beech, dogwood, honey locust, linden, mountain ash, sugar maple, cottonwood, and fruit trees.
Occasionally, leaf scorch is caused by a bacterial disease that can result in permanent damage or death to your tree.
Once the damage has happened, it's OK to remove the affected leaves, which should mostly be on the outside of the plant.
Stunted slow growth with yellowing leaves is a symptom of over-watering. Plants may suffer from leaf scorch or leaf burn. Water-soaked spots and blisters (Oedema) may appear on stems and leaves. The crown of the plant may rot.
You will want to trim the dead or scorched foliage after properly watering. Your plant is expending energy on attempting to keep the burnt parts alive. Clip these areas off so that the energy it produces will go to the areas of the plant that are still healthy.
Cause and Spread
This bacterium is spread by leafhoppers and treehopper insects, although it does not appear to be spread from tree to tree very rapidly.
The brown leaf tips will not turn back to green but you can trim the brown edges to get the plant back to looking healthy.
As sad as it is, brown tips are dead tips. You can't revive dead leaf cells, but you can make corrections and save the rest of your plant.
Sun sensitive plants need immediate shade after overexposure to the sun. If the plants are potted, then move them to a covered porch or indoors. If the plants are in the ground, then cover them with a fabric sun screen that is rated for landscaping. Watch the plants over the next few days to see how well they respond.
What is leaf scorch? Leaf scorch is a physiological disorder that presents as discolored tissues on the margins and sometimes between the veins of tree and shrub leaves. In severe cases the whole leaf turns brown, shrivels up and drops off. Leaf scorch is, in fact, a reaction to an unfavorable environment.
Plants vary in their response to fire. Fire readily kills some plants, rejuvenates others, and some may even require fire to exist. The manner in which plants are affected by fire is largely determined by their biological characteristics and fire behavior.
The good news is that most plants will bounce back between 7-14 days if they're given proper care (which includes rehydration). If this isn't possible because major damage was done or little healthy root system exists then expect about 2 weeks until improvement can be seen.
Once leaf scorch has occurred, there is no cure. The dehydrated portions of the leaf will not turn green again, but with proper water management, the plant may recover. Prevention of scorch needs to begin with winter watering.
Improper Fertilization
If you've recently fertilized your plant, this could be the culprit. Too much fertilizer or adding fertilizer to dry soil can burn the plant and cause crispy brown edges. Be sure to dilute any fertilizer in water and make sure that the soil is damp before fertilizing.
Once leaf tissue is scorched, the damaged areas will not recover; however, minor damage, while unsightly, will not kill the plant. Leaves with scorched margins may look unappealing, but they still help the plant with photosynthesis, creating food for new, undamaged leaves to emerge.
Sun-scorched plants can be cut back and fertilized and should recover with time (planting in the ground would be even better!).
If a small part of the leaf is burned, but the plant is still getting water and functioning, it's best to just let it be. In more severe cases where the leaves are completely brown and dry, it is best to remove them before disease takes over the rest of the plant.
Some common symptoms include: Browning and yellowing of the edges of the leaves. Wilting of the leaves, particularly in hot and dry weather. Reduced leaf size and curling of leaves.