Fertilizer Safety

What kinds of fertilizer should I know about?

Fertilizers come as dry granules, liquids, bagged organic products and manures and composts. They differ in how they behave, how they should be stored and how they affect people, animals and water. Some products are strong oxidizers and can add to a fire, and some release irritating dust or fumes.

Read the label and safety data sheet for every product. If a product is unfamiliar, ask your supplier or extension office what hazards it has before you buy it.

Many fertilizers look alike when the bag is torn or the label is gone, so mark opened containers with a permanent marker and the date. Pet and livestock access to open containers is a common cause of poisoning.

Why should I test the soil first?

A soil test tells you what your soil already has and what it needs. Guessing wastes money, can harm plants and increases the chance that nutrients wash into streams, ponds and wells. Your county extension office can explain how to collect a sample and where to send it.

Follow the lab's recommendations and the product label instead of using an amount you heard from a neighbor. Over-application is one of the most common and preventable mistakes.

Soil tests are inexpensive compared with the cost of unneeded product, and a test also shows pH, which affects how plants use what is in the soil. Your extension office can explain what the report means and what to do next.

How should I store fertilizer?

Keep fertilizer dry, cool and well ventilated, in a building with a solid floor, away from living areas, feed, seed, fuel and open flame. Keep bags off wet ground and away from pesticides and chemicals. Close and tape opened bags and store them where animals and children cannot reach them.

Do not store fertilizer near a well or surface water. Ask your extension office and local fire department about any special guidance for products with fire or explosion hazards, and about rules for larger quantities.

• Dry and well ventilated, with a solid floor
• Away from fuel, feed, seed and open flame
• Not near wells, ditches or ponds
• Opened bags sealed and out of reach

What protective gear do I need?

Wear the gloves, eye protection, long sleeves and respiratory protection the label recommends. Dust can irritate eyes, nose and lungs, and some products burn damp skin. Wash up after handling and before eating or drinking, and launder work clothes separately.

Clean up spreaders and tools after use, and do not leave residue where animals or children could reach it. Livestock can be poisoned by eating fertilizer left in a bag, a bucket or a pasture.

Do not apply near children or animals, and keep pets and livestock off treated areas for as long as the label states. Store unused product immediately instead of leaving bags in the truck bed or at the field edge.

How do I protect water and the environment?

Applying fertilizer before heavy rain, on frozen or saturated ground or too close to streams, ponds and wells can send nutrients into water. Ask your extension office or the Natural Resources Conservation Service about buffers, timing and practices that fit your land.

Keep spills off hard surfaces that drain to water. Sweep dry spills back into the bag if still usable or dispose of them properly, and do not hose them away.

What about manure and compost?

Manure and compost are fertilizers too. Fresh manure can carry germs, so wash hands, keep it away from produce and follow guidance from extension on timing before harvest. Piles that are large, wet or hot can create gases and heat, and should be managed with care.

Keep piles away from wells, streams and property lines, and cover or contain them where runoff is a concern. Local rules about manure storage and application vary, so ask your county extension office or conservation district.

Test the soil where manure has been used for years, since nutrients can build up unnoticed. Your extension office can tell you how to account for manure when you plan your fertilizer for a season.

What if there is a spill, fire or exposure?

For a fire in a fertilizer storage area, evacuate and call the fire department, and tell them what is stored there. Do not try to fight a large fire yourself. For skin or eye contact, follow label first aid and seek medical help. For swallowing or breathing in a product, call poison control or emergency services.

If an animal may have eaten fertilizer, call your veterinarian right away and bring the label. Quick action matters, and early calls give the best chance.

Last reviewed: November 12, 2026. Written by the Homestead & Small Farm Editorial Team. See our editorial policy.