Diatomaceous Earth (DE)
Quick Facts
- Type
- Mineral / Physical
- Source
- Fossilized remains of diatoms (microscopic aquatic organisms); food-grade only
- OMRI Listed
- Yes ✓
- Bee Safe
- Yes
- Pet Safe
- Yes
- Residual
- Effective as long as it stays dry; loses effectiveness when wet
- Best For
- Crawling insects in dry conditions. Perimeter barriers around raised beds. Slug deterrent rings around plants.
What Is Diatomaceous Earth (DE)?
Microscopic silica particles abrade the waxy cuticle of insects and absorb lipids from the exoskeleton, causing death by desiccation. Purely physical action — no chemical toxicity and no resistance development possible.
Source: Fossilized remains of diatoms (microscopic aquatic organisms); food-grade only
What Pests Does Diatomaceous Earth (DE) Kill?
Diatomaceous Earth (DE) is effective against the following pests:
How to Apply Diatomaceous Earth (DE)
Best for: Crawling insects in dry conditions. Perimeter barriers around raised beds. Slug deterrent rings around plants.
Avoid for: Wet climates, irrigated gardens, or anywhere it cannot stay dry. Do not dust on flowers where bees land.
Residual activity: Effective as long as it stays dry; loses effectiveness when wet
Safety Profile
| Category | Rating |
|---|---|
| Bee Safety | 🟢 Safe for bees |
| Pet Safety | 🟢 Safe for pets |
| Overall Rating | Safe — Safe for kids, pets, and bees when used as directed |
Why Isn't Diatomaceous Earth (DE) Working?
If Diatomaceous Earth (DE) isn't delivering results, check these common failure modes:
Gets wet — moisture eliminates all effectiveness; must reapply after rain or irrigation
Wrong grade — pool-grade DE is heat-treated and dangerous to breathe; only use food-grade
Kills indiscriminately — will harm beneficial ground-dwelling insects too
Inhalation risk — wear dust mask during application; irritates lungs
DIY Diatomaceous Earth (DE) Recipe
Apply food-grade DE as a thin dust ring around plant stems, along raised bed edges, or directly on dry foliage. Use a hand duster for even application. Reapply after every rain.
Best Diatomaceous Earth (DE) Products
Harris Food Grade DE
PowderComes with applicator duster — best value
Earthborn Elements DE
PowderResealable bag, food-grade certified
St. Gabriel Insect Dust
PowderPre-loaded puffer bottle