Julie Clopper / Shutterstock.com Garden Chemicals Illegal in Garbage or Drains Hazardous Waste Julie Clopper / Shutterstock.com Never Pour Down the Drain Garden chemicals, such as weed killer and fertilizer, can never be dumped down storm drains or in the trash. Sewage drains are not equipped to handle these chemicals. Don't Water Grass After Absolutely do not water the grass after applying garden chemicals. This runoff ends up in water drains that can contaminate lakes and rivers. It also makes your pesticides less effective against pests. Don't Use if It's Going to Rain Avoid using chemicals before a storm; if you do, they will be washed down storm drains, or leach into the soil, once it starts raining. Rinse Empty Concentrate Containers Containers that held concentrate need to be rinsed out three times before they are thrown in the trash: to do this, add remaining spray to the tank. Next, add water into the container, swirl and then transfer to the spray tank. Finally, repeat these steps twice. Ready-To-Use Containers Empty containers that held ready-to-use chemicals can be thrown in the trash without rinsing them out. Ways to Reduce Avoid Purchasing Concentrates Consider purchasing ready-to-use products. Purchasing concentrations to dilute on your own can expose the body to harmful chemicals. Also the use of under-diluted chemicals is more damaging to the air, water and soil. Buy What You Need Reduce the impact of garden chemicals on the environment by buying only what you need. Also give away any leftover, which saves you the hassle of disposing of them as Household Hazardous Waste.