How To Use a Pesticide Sprayer

When tackling DIY pest control, at some point you’ll likely need to use a pesticide sprayer. Whether you’re using insecticides, herbicides, or fungicides, understanding the basics of a sprayer can make your weed control, lawn care, and garden maintenance a breeze.

Pesticides come in many forms — dust, granules, vapor, and more. The liquid variety is the most common and effective. While you can buy ready-mixed insect killers, the most powerful options are typically sold as concentrated liquids. This means you’ll need to mix a few ounces of the pesticide with water before applying it using a sprayer. You’ll likely use a gallon sprayer to create the correct mixture before using it on your treatment area.

Think of a pesticide sprayer as a tool that helps you mix and apply pesticides efficiently. A sprayer usually has a tank where you mix the concentrated pesticide with water. After mixing, you pressurize the tank with a manual pump or a powered pressurizer. The liquid is then ready to be sprayed through the tank sprayer.

In this article, I’ll talk about how to use and clean a pesticide sprayer. I’ll also talk about the different types of sprayers so you can use this home tool well.

What Is a Pesticide Sprayer?

Before we dive right into how to use a pesticide sprayer, it’s imortant to understand how they generally work. I’ll break it down to the most simple level.

A sprayer has a tank where you mix the concentrated pesticide with regular water.

Once the liquids are in the sprayer, you pressurize the tank by pumping air into it. This is usually done with a manual hand pump, but fancier sprayers have powered pressurizers. The air compresses at the top of the tank, which puts downward pressure on the liquid.

With the pressure pushing down on the liquid, there’s only one place for it to escape — up the straw that leads to your spraying wand.

Now that you have a basic understanding of how a sprayer works, I’ll go into more detail on how to use a pesticide sprayer. Later, I’ll examine the different types of sprayers along with their pros and cons.

How To Use a Pesticide Sprayer

Using a pesticide sprayer effectively involves a series of important steps to make sure you get the best results safely. This section examines the five essential steps to using a pest sprayer correctly. You’ll start by learning how to check and prepare your equipment, mix the pesticide properly, and pressurize the sprayer. I’ll also cover how to adjust the nozzle for different spray patterns and the crucial safety tips for applying pesticides. As you continue reading, you’ll gain detailed insights into each step, so you can handle your pest control tasks with confidence.

1. Check the Equipment

The first thing you should do is check your spraying equipment for damage or leaks. Partially fill the sprayer with water and pressurize it to make sure it maintains pressure.

Spray a little of the water to check for leaks. If your equipment can’t hold pressure or is leaking chemicals, you need to repair or replace it before continuing.

Pesticides are safe to use when used as directed by the label. But broken equipment may mean you are leaking pesticide where you don’t want it.

2. Mix the Pesticide

Once you’re satisfied that your equipment is working properly, it’s time to mix in the pesticide. The best way to do this is to fill the tank halfway up, then add the pesticide to the water. Once that’s done, top up the water to get the prescribed level.

For most DIY users at home, this will be a one gallon tank. Pesticide labels will instruct you on how many ounces to add to a gallon tank.

This procedure makes sure that the pesticide mixes thoroughly with the water and helps you avoid splashbacks while filling.

You can’t always predict how fast and hard the water will come out of the faucet or hose. If you add pesticide first and then spray with a high-pressure hose, you risk splashing concentrated pesticide on your face or skin.

Always follow the manufacturer’s instructions on diluting the pesticide. It can be tempting to mix your pesticide stronger than the manufacturer recommends, but it’s unnecessary and unsafe.

The manufacturer specifies the dilution rate that determines how safe pesticides are for use. If you start making stronger mixes, you can’t be sure it won’t be harmful to your health. Plus, it’s a waste of pesticides. Pesticides are diluted to kill bugs, using more won’t make them any more dead.

It’s also worth mentioning here that there is a class of pesticides called “wettable powders”. Add these powders to water and keep them suspended in the liquid. While they are sprayed similar to liquid pesticides, when these powders dry they revert to powder form.

If you’re using a wettable powder, make sure that the spray equipment you are using can handle these formulas. Make sure to keep agitating the spray tank as you spray so the powder stays suspended in the liquid. Some cheaper sprayers clog when using powders or heavy oil-based sprays.

3. Pressurize the Sprayer

Most sprayers work by keeping the liquid inside under higher pressure than the outside atmosphere. This high pressure causes the liquid to try to get out of the sprayer via the straw that connects to your spraying wand.

When you press the trigger, the pressurized liquid shoots out of the sprayer and goes where you direct it.

Many sprayers achieve this pressure differential with a manual pump. By pressing down on the handle, you pump air into the sprayer. A specialized valve keeps the air from getting out, so the pressure inside the container builds. These manual sprayers are usually the cheapest and most common option for spray equipment.

If spraying manually, be careful not to pump too much air into the tank. The greater the pressure, the higher the rate at which the pesticide comes out of the container. This can cause the pesticide to splashback off hard surfaces and get onto your skin, where it may be absorbed into your body.

Spraying at too high of a pressure causes you to dispense pesticide much faster as well, which adds to the cost of any treatment you’re doing.

If the pressure of your sprayer is too high, you can’t control your pesticide, and it can end up in places you don’t want it to go. Many pesticides can be extremely harmful to non-target organisms like fish or honey bees. It’s very important to make sure anything you spray doesn’t end up going down the drain or contaminating the water source.

The best way to avoid this is to make sure you keep the pressure low. If you’re feeling much resistance in the handle as you pump, you’re probably putting too much pressure on it.

3. Adjust the Nozzle

Most sprayers come with an adjustable nozzle. By twisting the nozzle, you can change the spray pattern to best suit your needs. Different spray patterns are useful for different types of applications.

Here are some common patterns:

• A thin pin stream gives a narrow and highly targeted stream that is great for applying to narrow gaps such as cracks and crevices. Keep in mind that the smaller the pin stream, the higher the pressure as the liquid gets forced out of a smaller hole. This is useful for achieving greater penetration of an underground ant colony or a wasp nest, but you need to be more careful for splashback.
• A fan spray gives a wider, flatter spray that enables you to cover a broad area in less time. This is useful for applying pesticides in an even coat along baseboards, foundations, soffits, and other areas. If you’re performing a preventative pest spray or perimeter treatment, this is the setting you’ll probably use the most.
• A mist setting allows you to apply pesticide evenly in a very fine spray that travels easily in the air. This can be useful for treating bushes and vegetation with a light coat of pesticide that reaches everywhere. It’s great when you want to coat all sides of a tree or bush, but be careful to only use the setting on days with no wind. It’s very easy for a light mist to travel and end up in places you don’t want it to go.

4. Applying the Pesticide

Finally, it’s time to spray. Where you’re spraying the pesticide is going to depend on what pest you’re trying to control. I’d highly recommend looking at our pest-specific guides for those tips. You can easily find them in the menu bar or by searching the site.

Application Safety Tips

Always wear safety equipment when applying any pesticide. At the minimum, this should include gloves that are rated to stand up to pesticides, and I always recommend glasses or goggles too.

Be aware that some oil-based pesticides can easily dissolve latex gloves. You should also wear long sleeves and pants to protect your skin. Skin absorption is the most common way that people end up sick from pesticide usage.

A respirator or mask will help to protect your lungs, but make sure you use one that’s suitable for the pesticide you’ve chosen. A dust mask won’t stop you from breathing pesticide vapor, and you’re better off with a proper respirator that uses canister filters.

Never spray directly above your head. What goes up must come down. If you need to spray an area above you, get a ladder and make sure to stand to one side so dripping pesticide won’t fall down on you.

You should avoid spraying on a windy day as well. Wind can carry pesticides a long way from where you intended to apply them. This can damage the environment. Make sure the pesticide stays where you want it by spraying on calm days with winds of no more than a couple of miles per hour.

Don’t spray in the rain either. This may seem obvious, but spraying during or immediately before rain causes the pesticide to be washed away and end up in rivers and lakes. It also won’t kill many pests as the rain heavily dilutes it. Ideally, if you’re spraying outside, do it on a day when you can be confident there won’t be any rain for least 24 hours after you’re finished.

5. Cleaning Up

Just because the spraying is over doesn’t mean your work is done. After finishing a treatment, you need to release the pressure in your spray tank. Otherwise, the pressurized pesticide will damage the seals and the tank may start to leak.

Generally, spray tanks have a special pressure release valve to let the air out safely. Avoid unscrewing the handle of the pump sprayer as you did to fill the tank. Doing so might force the pressurized pesticide out of the tank and spray it directly at you.

Don’t use spray tanks for long-term pesticide storage, as they aren’t designed for it. Pesticides lose potency quickly once you dilute them inside the spray tank. Also, many jurisdictions prohibit storing pesticides in spray tanks. To comply, make sure to empty the tank after use.

Calculate the amount of pesticide you need for the job and mix only that much. By the time you finish, the tank will be empty and ready for storage.

If you can’t avoid leaving some pesticide in the tank, dispose of unused pesticides properly. Pour the leftover pesticide onto soil far from water sources or transfer it to another container. Then take it to a waste disposal facility. Always check the manufacturer’s recommendations and local pesticide laws to guarantee you handle everything correctly.

Before storing your spray equipment, triple rinse it with water to remove any pesticide residue. Clean the outside of the tank as well to remove any remaining pesticide or dirt. These steps will help your spray equipment last much longer.

Different Types of Pesticide Sprayers

You’ll find lots of different types of pesticide spray equipment on the market. The best one for you is going to depend on the nature of your pest problem and how much spraying you intend to do. Here are the main types.

Hand Pump Sprayers

These sprayers are some of the cheapest and easiest to use. Designed to be carried in one hand while you use the other hand to direct the spray, the capacity of these sprayers is typically in the 1–2 gallon range. You can find sprayers like this at any hardware store, and they can deal with most household pest problems.

Pros:

• Cheap to buy and repair
• Easy to use
• Easy to find
• Enough capacity for most home pest problems
• No motor or other expensive and unreliable parts

Cons:

• Low capacity means you may need to refill many times if spraying a large area
• Cheaper construction may not be as durable as more expensive sprayers
• Low spray rate means treatments take longer

Backpack Sprayers

Backpack sprayers work on the same principle as hand pump sprayers. However, they have a greater capacity and can be comfortably carried. Backpack sprayers usually hold around four gallons of diluted pesticide, although some can be a little bigger.

The great advantage of this capacity is that you don’t need to fill it up as often. This can cut down on the time it takes to perform the pesticide spray of a large area.

Backpack sprayers are sometimes pressurized by hand, just like hand-pump sprayers. Some of the more expensive models have a motor that handles the pressurization for you. This motor can be powered by an electric battery or even by gas.

Although these sprayers are more expensive, they cut down on fatigue by saving you from having to pump to pressurize the tank constantly. They also offer a more consistent spray by keeping the pressure at a preset level.

Pros:

• High-capacity means less time spent refilling
• More comfortable to use on large sprays
• Powered models reduce user fatigue
• Hand powered models can be relatively cheap

Cons:

• More expensive than hand pump sprayers
• Powered models are expensive both to buy and maintain
• Motors add complexity and may require additional maintenance
• Four gallons of diluted pesticide weighs over 33 pounds, so you need to be physically strong enough to carry that weight while spraying

Hose End Sprayers

These single-use devices come with the pesticide already inside. They’re designed to be attached to the end of a garden hose and sprayed over a large area. The device mixes the pesticide with water at the specific rate as you spray so there’s no measuring. Once the pesticide is all used up, the sprayer can be easily disposed of.

Pros:

• Extremely easy to use, with no mixing necessary
• Cheap to buy
• No maintenance needed

Cons:

• Less control over the spray rate and pattern
• Can be hard to find quality pesticides that can be used like this

Large Capacity Sprayers

Professional pesticide applicators use these sprayers. The smallest sprayers resemble small water tanks on wheels, while larger ones mount in the back of a truck or on an ATV. They deliver large amounts of pesticide over broad areas and serve agriculture and professional pest control.

• Reduce user fatigue by not needing to be carried
• High-capacity means less refilling needed
• Can be used in areas without a reliable water supply, at least until the tank runs out
• Longer hoses allow treatment of a much larger area.

Cons:

• Can be very expensive.
• Maintenance is necessary to keep the motor and hoses in good condition.
• Filling takes a long time and requires huge amounts of both water and pesticide.
• Generally only suitable for professionals who spray large areas outdoors.

Spraying tips

Never carry a sprayer by its wand or hose, as this can damage the sprayer. Also, never store pesticide inside a sprayer. This practice may be illegal and can damage internal seals and valves. Make sure that you use all the pesticides you mix for treatment.

Avoid exposing the sprayer to extreme temperatures. Heat causes the air inside a sprayer to expand, increasing the pressure beyond the appropriate level. Extreme cold can freeze the pesticide inside a sprayer, causing it to expand and rupture the wand, hoses, or even the tank itself.

Be aware of the wind when spraying. You shouldn’t spray on a windy day, but even a light breeze can create problems. Make sure the wind blows away from you to prevent the pesticide from blowing back onto you.

Finally, leave an air gap when filling a spray tank. If the water level in a spray tank rises above the end of the hose used to fill it, you risk backflow. This condition occurs when the hose creates a siphon that draws the pesticide back into the water source. Prevent backflow by always keeping a gap between the end of the fill hose and the water level inside the tank.

Top Reasons To Use Concentrated Pesticides

Professionals and homeowners alike appreciate concentrated pesticides for several reasons. One of the most significant is the cost. Buying a concentrated pesticide and mixing it with water to achieve the correct concentration is much cheaper than purchasing a pre-mixed product. With pre-mixed options, you end up paying extra for water or other substances that dilute the pesticide.

Additionally, concentrated pesticides are easier to store. This is important for pest control companies handling numerous treatments each week. The compact nature of concentrated pesticides minimizes the storage space required.

Finally, concentrated pesticides generate less waste. A quarter-gallon bottle of concentrated pesticide can produce hundreds of gallons of usable product. It’s a more environmentally friendly choice compared to using numerous aerosol cans for the same amount of pesticide.

Final Thoughts

Now you understand how to use a pesticide sprayer properly for your pest control efforts. By thoroughly checking and preparing your equipment, making sure it is free of damage and leaks your off to a good start. Mixing the pesticide correctly, pressurizing the sprayer, and adjusting the nozzle for your specific needs are crucial steps to see results. Remember to follow safety guidelines meticulously, including wearing protective gear and avoiding application in bad weather conditions. Properly clean and store your equipment so it will operate properly and last longer.

Choosing the right type of pesticide sprayer for your needs can impact the effectiveness and efficiency of your pest control tasks. Hand-pump sprayers offer affordability and ease of use for small tasks, while backpack sprayers have greater capacity and comfort for large areas. Professional-grade sprayers cater to large and demanding tasks, offering high-capacity and less work. Each type of sprayer brings unique advantages. You can now select the best tool based on the size and difficulty of your job.