Concrete Dust Killing New Cedars: Salt Toxicity

Two weeks of concrete cutting dust (sodium hydroxide, high pH) on 6-foot cedars causes salt/alkalinity burn. Sodium is toxic to plants; the dust raises soil pH and desiccates foliage.

Immediate Action

1. Thoroughly hose down foliage and soil daily for 1–2 weeks to leach salts.
2. Apply gypsum (calcium sulfate) at 10–20 lbs/100 sq ft to displace sodium; water in.
3. Mulch heavily to reduce evaporation and further salt concentration.

Reality

Severely browned centers may not recover. No “revive” product reverses salt kill. Prevention: cover plants with tarps during concrete work; rinse immediately after.