Spinosad
Quick Facts
- Type
- Microbial-derived
- Source
- Fermentation metabolites of the soil bacterium Saccharopolyspora spinosa
- OMRI Listed
- Yes ✓
- Bee Safe
- No — apply in evening
- Pet Safe
- Yes
- Residual
- 7-14 days on leaf; breaks down in sunlight within 1-2 days on exposed surfaces
- Best For
- Thrips, leafminers, caterpillars, and fire ants. Broad-spectrum organic workhorse.
What Is Spinosad?
Causes nervous system excitation by activating nicotinic acetylcholine receptors and GABA receptors simultaneously. Insects exhibit involuntary muscle contractions, paralysis, and death within 24-48 hours. Works by both contact and ingestion.
Source: Fermentation metabolites of the soil bacterium Saccharopolyspora spinosa
What Pests Does Spinosad Kill?
Spinosad is effective against the following pests:
How to Apply Spinosad
Best for: Thrips, leafminers, caterpillars, and fire ants. Broad-spectrum organic workhorse.
Avoid for: Never spray on open flowers or when bees are actively foraging. Apply in evening only.
Residual activity: 7-14 days on leaf; breaks down in sunlight within 1-2 days on exposed surfaces
Safety Profile
| Category | Rating |
|---|---|
| Bee Safety | 🔴 Toxic to bees while wet |
| Pet Safety | 🟢 Safe for pets |
| Overall Rating | Caution — Use with caution — timing and technique matter |
Why Isn't Spinosad Working?
If Spinosad isn't delivering results, check these common failure modes:
Applied during bee foraging hours — toxic to bees on contact while wet
Resistance development from overuse — rotate with Bt or other modes of action
Insufficient coverage — must contact or be ingested by target insects
Best Spinosad Products
Monterey Garden Insect Spray
ConcentrateMost popular spinosad product for home gardens
Captain Jack's Dead Bug Brew
RTU SprayReady-to-use for small applications
Conserve Fire Ant Bait
Granular baitSpinosad-based fire ant control