Clean a chemical sprayer by emptying it fully, rinsing the tank with clean water, flushing hoses and nozzles, and cleaning filters separately.
For the full breakdown, see our best Acid Resistant Sprayer guide.
The steps below follow guidance from Nebraska Extension and Arkansas’s MP532 manual.
Before you start, one rule matters most: finish with an empty tank. Leaving chemical sitting in the tank is the most common mistake, and it makes every later step harder.
Why Cleaning Right After Use Matters
Chemical residue does more than clog parts. Some herbicides bind to plastic and rubber, contaminating a completely different product next season. Nebraska Extension notes that herbicide residue is the problem most often linked to damaged crops from a previously used sprayer. Beyond crop safety, regular cleaning extends the life of seals, diaphragms, and nozzles.
The Step-By-Step Cleaning Process
Cleaning a sprayer comes down to seven actions. Follow them in order, and you will not miss a spot where residue hides.
- Empty the tank completely. Spray remaining product onto the treated area whenever legal and practical. If not, pour it back into its original container following label instructions.
- Release pressure before opening anything. Open the lid slowly and point the nozzle away from your face. Pressure can build even after the tank seems empty.
- Rinse the tank with clean water. Nebraska Extension recommends filling to about 10% capacity. Swirl so water reaches every wall and the bottom corners.
- Flush the system thoroughly. Run rinse water through hoses, wand, and nozzle as when spraying.
- Remove and clean the filters and screens. Strainers, nozzle screens, and tips collect the heaviest residue. Take them apart and rinse under running water, using a soft brush if needed.
- Wash the outside of the sprayer. Wipe the tank exterior, wand, and hose with warm water and mild soap. Avoid aggressive cleaners or abrasives, which damage seals and plastic.
- Drain and dry the system upside down. Open the lid, remove the nozzle, and air dry completely before storing. This prevents mold and keeps leftover water from diluting your next mix.
When finished, the rinse water is still chemical waste. Dispose of it per the manufacturer’s instructions and Safety Data Sheet, and never clean equipment where runoff can reach wells, waterways, crops, or play areas.
Do Different Chemicals Need Different Cleaning?
Sometimes, yes. Water alone does not break down every active ingredient. New South Wales DPI guidance shows that different herbicide classes need different cleaning solutions and soak times—some require ammonia or a specialized cleaner. Check the label or Safety Data Sheet for a decontamination procedure before cleaning. If it lists a specific cleaner or soak time, follow that instead. This matters most for persistent herbicides, which damage unrelated crops later. Acid-based products also change the math: standard water rinsing may not neutralize them, and a rinse with baking soda or garden lime is sometimes recommended.
| Step | What To Do | Common Mistake |
|---|---|---|
| Empty | Spray leftover product onto the treated area | Leaving chemical sitting in the tank |
| Depressurize | Open the lid slowly with the nozzle pointed away | Opening while pressure remains inside |
| Rinse | Fill to 10% capacity and swirl to reach all walls | Using too little water to cover the interior |
| Flush | Run water through hoses and nozzle for 5–15 minutes | Rinsing the tank but skipping the lines |
| Clean parts | Remove filters, screens, and nozzle tips; rinse separately | Leaving residue in the parts that clog first |
| Wash outside | Use warm water and mild soap on all exterior surfaces | Using abrasives that damage seals and plastic |
| Dry | Drain fully and air dry with the lid open | Storing a wet sprayer that grows mold |
FAQs
Can I clean a sprayer with bleach?
Only if the chemical label specifically allows it. Bleach can damage seals, gaskets, and plastic, and it reacts dangerously with some pesticides. Plain water followed by warm soapy water handles most residue. When a product needs more, the label will name the exact cleaner.
How often should I deep-clean my sprayer?
At minimum, flush with clean water each time, and do the full disassembly and filter cleaning after any herbicide application.
What do I do with leftover rinse water?
Treat rinse water as chemical waste, not plain water. Spray it onto the same treated area, following the label’s disposal instructions. Never pour it down a drain, onto pavement, or anywhere runoff could reach a well, stream, or garden. Check the Safety Data Sheet for product-specific rules.
References & Sources
- Nebraska Extension. “Cleaning Pesticide Application Equipment.” Provides the 10% tank rinse and five-minute flush guidance.
- New South Wales DPI. “Cleaning Spray Equipment.” Shows that herbicide classes require different decontamination solutions.
- GRDC Spray Application Manual. “Suggested Cleaning Process.” Details the full rinse-and-flush sequence for spray equipment.