Composting Grass Clippings After Scotts Bonus S: Why It's Unsafe

You've used Scotts Bonus S (23-9-4 with atrazine) for years and want to compost clippings for vegetable beds. Don't. The herbicide residues persist and can damage or kill garden plants.

The Atrazine Problem

Bonus S contains 1.055% atrazine, a triazine herbicide linked to groundwater contamination and endocrine disruption. Howard Garrett (The Dirt Doctor) calls it the #1 fertilizer to avoid. Atrazine doesn't break down quickly in compost — it can survive and transfer to food crops.

Persistent Herbicide Legacy

• Clopyralid and picloram (in other products) survive composting, pass through animals, and kill plants in manure.
• Scotts recalled Bonus S Max (2008) for label inaccuracies; Miracle-Gro Shake 'n Feed for unregistered herbicide.
• HARC research confirms: many modern herbicides resist degradation.

What to Do Instead

• Stop using Bonus S. Switch to organic lawn care.
• Do not compost treated clippings — bag and dispose.
• Get a soil test; build soil health with compost, not chemicals.
• Consider health risks: atrazine linked to cancer, birth defects.

A perfect lawn isn't worth contaminated compost or family risk.