What Do Organic Farmers Use for Pesticide? | The Real List

Organic farmers use pesticides derived from natural sources, but only those approved under USDA National Organic Program rules.

Whether you’re tending a backyard vegetable patch or shopping at a farmers market, the question of what organic farmers use for pesticide comes down to one document: the USDA’s National List. Organic farming isn’t pesticide-free farming—it’s farming with a strictly limited toolbox. Most synthetic chemicals are out, most natural ones are in, and everything else sits on a review list. Here’s what that means in practice, which substances actually get sprayed, and where the lines are drawn.

How The USDA Decides What Organic Farmers Can Spray

The National Organic Program (NOP) sets the rules, and they’re codified at 7 CFR 205. The National List, found in sections 205.601 and 205.602, is the master reference: it names the synthetic substances that are allowed and the natural substances that are prohibited. Everything else defaults to the basic rule—natural is generally permitted, synthetic is generally banned.

Before an organic grower uses any pesticide, the substance must check three boxes:

• It’s on the National List for the intended crop use.
• The operation’s certifying agent approves it as part of the organic system plan.
• The label complies with EPA registration rules for sale and use in the U.S.

This isn’t a casual checklist. The USDA’s allowed and prohibited substances list runs dozens of pages and gets updated through public comment periods. Growers also consult OMRI (Organic Materials Review Institute) or state programs like WSDA when they’re unsure about a product.

What’s On The Allowed List: The Common Organic Pesticides

In practice, organic farmers reach for a rotating cast of biological and mineral-based products. These are the workhorses you’ll find in organic orchards, row crops, and high tunnels alike:

• Bacillus thuringiensis (Bt) — a soil bacterium that targets caterpillars and worm pests specifically
• Spinosad — derived from soil bacteria, effective against thrips, leafminers, and fruit flies
• Sulfur and copper compounds — long-standing fungicides for powdery mildew, scab, and blight
• Horticultural oils and insecticidal soaps — suffocate soft-bodied insects like aphids and mites
• Ferric phosphate — iron-based slug and snail bait
• Vinegar (acetic acid) — used as a contact herbicide for young weeds
• Bacillus subtilis — a beneficial bacterium that suppresses fungal diseases

One distinction matters: “natural” and “harmless” are not the same thing. Copper, for instance, is crucial for organic disease control but accumulates in soil and can harm aquatic life. Even approved substances demand normal handling precautions and label compliance.

The Trap To Avoid: Thinking Organic Means No Pesticides

It’s a widespread misconception. Research bears this out: organic fields are about 30 percentage points less likely to be sprayed than conventional fields, but when organic growers do spray, application rates can look similar to conventional ones. The difference isn’t how much gets used—it’s which substances are available.

What’s banned in organic production tells the real story. Glyphosate (Roundup), atrazine, organophosphates, methyl bromide, arsenic-based compounds, and nicotine-based pesticides are all out. So are synthetic fertilizers and most synthetic pesticides not on the National List. This prohibition matters as much as the allowed list itself.

For home gardeners, the practical takeaway: if you want to stay within organic rules, verify each product label against the National List guidance or look for OMRI certification. And if you’re ready to buy, our tested roundup of organic insecticide for vegetables breaks down which products actually work for common garden pests.

Prevention Comes First — Spraying Is The Last Resort

Organic pest control isn’t a spray-first system. The NOP requires growers to start with prevention: healthy soil, crop rotation, resistant varieties, physical barriers like row covers, regular scouting, and mechanical weeding. Pesticides enter the picture only when those measures fall short.

That’s a meaningful difference from conventional systems that often use preventive broad-acre applications. Organic growers tend to target specific crops and specific problem spots rather than blanket-spraying entire fields. The EPA’s own guidance on organic farming and pesticides makes this prevention-first hierarchy explicit.

When prevention fails, the allowed list kicks in. But the decision to spray isn’t the grower’s alone—it’s a documented step in an approved organic system plan, reviewed by a certifying agent who can say no.