Azalea Yellow Leaves: Fertilizer Won't Fix pH Fast—Use Aluminum Sulfate Instead

Yellow leaves = iron unavailable due to high pH. Acidifying fertilizers work too slowly (years).

Fast Fix

Dissolve 8 oz aluminum sulfate (drugstore alum) in 1 gal water, drench root zone. Drops pH ~1 point fast.

Confirm cause: poor roots, nematodes, or pH? Alum only helps if pH is the problem.

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