Correcting Magnesium Deficiency in Orange Trees with Epsom Salt

Yellowing older leaves and dying upper branches on orange trees may indicate magnesium deficiency—but first rule out spider mites (check leaf undersides for tiny red dots and fine webbing) and watering issues (both over- and under-watering cause yellowing).

Safe Epsom Salt Application

Use magnesium sulfate (Epsom salt) at 1 tablespoon per gallon of water or a light sprinkle (⅛-¼ cup) evenly distributed under the canopy, extending 1-2 feet beyond the drip line. Keep 3-4 inches away from the trunk.

Best Practice: Soaker Hose Method

1. Run soaker hose in circles around tree for 30 minutes (or two 15-min cycles 30 min apart) to pre-wet soil.
2. Sprinkle Epsom salt lightly under canopy.
3. Restart soaker hose for 30-45 minutes to dissolve and distribute nutrients.

If using a handheld hose, wet soil slowly first, then apply salt solution, then water deeply. Multiple light applications over the season are safer than one heavy dose—excess salt damages roots.

Alternative Magnesium Sources

Dolomitic lime supplies magnesium and calcium while raising pH (use only if pH is low). Avoid chemist-grade magnesium; stick with agricultural Epsom salt or dolomitic lime.