Burnt Avocado Leaves: What Causes Avocado Leaf Burn

avocado leaf burn
avocado leaf burn
(Image credit: ArmorelScilly)

When the tips of your avocado leaves look scorched, but the sun isn’t hot, you may be perplexed. Why are my avocado leaves burnt, you may ask. Avocado leaf burn doesn’t always result from high-voltage sunshine. If you want to understand the causes for burnt avocado leaves, read on.

Why are My Avocado Leaves Burnt?

Avocado leaf burn is fairly easy to recognize in avocado trees. You’ll see dry and scorched avocado leaves, and the damage is especially noticeable around the tips. Leaf burn also causes the affected leaves to fall from the tree well before normal dormancy. The condition makes it look as though extra-hot sunshine has burnt avocado leaves on your trees. This condition can also appear when the sky is cloudy, and the weather is cool or mild. Given the absence of dramatic sunshine, you may wonder what is causing the scorched avocado leaves. Burnt avocado leaves can be caused by many factors other than sunshine. When avocado tree leaves brown at the tips and the edges, it is usually associated with an accumulation of salts in the soil. Dry conditions can also play a role. Dry conditions contributing to avocado leaf burn can include inadequate irrigation. Dry winds can also desiccate the foliage and frost may play a part as well.

Preventing Avocado Leaf Burn

How do salts get in the soil? If you live near a salty body of water, the connection is pretty obvious. Avocados are very sensitive to salts, and they accumulate sodium and chlorides more readily than other trees. A good way of preventing avocado leaf burn is to give the tree regular deep waterings. That washes the salt out of the soil. Forget light irrigation. It doesn’t offer sufficient water to leach out the accumulated salts. Avocado leaf burn can also be caused by excessive fertilizer applications. Deep watering helps leach out fertilizers too. Be sure to add measured amounts of fertilizer per label directions. Desiccation can also be reduced or prevented by appropriate irrigation. Many homeowners trying to provide good irrigation place the garden hose near the tree trunk and let it run. However, mature avocado trees have a canopy that spreads far in all directions. The roots extend as far as the canopy and sometimes farther. To water these roots, you need to irrigate at the outside edges of the canopy, not near the trunk.

Teo Spengler
Writer

Teo Spengler has been gardening for 30 years. She is a docent at the San Francisco Botanical Garden. Her passion is trees, 250 of which she has planted on her land in France.