White and Green Mold in New Flower Beds: Soil Texture Issue

Question: New flower beds in Arizona with purchased soil (organic and Miracle-Gro). Plants dying, scales on palms, now white/green powdery mold throughout soil. Treat or replace soil?

Root Cause

Don't remove/replace soil or add different textured soil on top. Amend existing soil by blending ≤1/3 organic matter uniformly. Mold suggests soil stays too wet too long.

Fix

Remove plants, till new soil into old soil, replant. Fungus likely not harmful, but wet conditions cause root rot. Bayer product should cure scale. Consult local independent nurseryman for future projects—they prevent problems; box stores just replace dead plants.