Chloride/Tip Burn

• Tip burn is the result of too much sodium chloride in the leaves or by an inadequate water supply. Sometimes irrigation waters are high in chloride, which can also lead to tip burn. If the leaves look burned at the tips and the problem appears to spread down its edges, then chloride is the problem.
  
  

Sodium Scorch

• Sodium scorch is indicated by necrotic spots on the leaves. Necrosis is the death of small patches of leaf tissue, leaving the leaves with a scorched appearance. These spots are often found in conjunction with tip browning or marginal browning of the rest of the leaf.
  
  

Leaching

• If your plants are salt-stressed, the best way to fix the problem is to begin a regular leaching schedule to wash the salts out of the soil. This involves keeping the hose on a mature tree for 24 hours. If your avocado is potted, water it deeply every week or so, letting the water run out the drainage holes for several minutes.
  
  

Mulch

• Because avocados like fairly moist, very well draining soil, mulching is a good idea. That said, mulches that do wonders for vegetable gardens can easily harm avocados. Never add manure or mushroom compost as mulch or as a backfill amendment when planting or potting an avocado tree, as they are too high in salts and ammonia; instead, the San Diego Master Gardeners recommend chipped wood.
  
  

Considerations

• Avocado trees are incredibly sensitive to salt and salt build-up in their irrigation water. Sometimes the problem is difficult to treat, especially if your irrigation water has a high mineral content. Avocado growers in southern California, for instance, get their irrigation water from the Colorado River, which travels far to reach their trees and picks up lots of minerals on the way. Salt-stressed trees produce smaller fruit. Because a tree drops its dead, salt-burned leaves, it spends extra energy the following spring regrowing them. That’s energy that won’t be spent on fruit production--resulting in smaller fruits.