How to use a hose-end sprayer

A hose-end sprayer screws onto your garden hose and mixes a product with water as it sprays. It’s fast, there’s no tank to pump, and for liquid fertilisers and wetting agents over a whole lawn it’s hard to beat. The catch is that it’s only as accurate as your setup and your walking pace. This guide covers choosing the right type, setting it up from the label, checking it with water, spraying evenly, and cleaning up.

When a hose-end sprayer is the right tool

Hose-end sprayers suit products that are applied to the whole lawn in a large volume of water, such as liquid fertilisers, seaweed and soil conditioners, and wetting agents. They are less suited to products whose label gives a precise water volume per area, or that should only go on individual weeds. For those, a calibrated pump sprayer gives you far more control.

Before you start, check the product label says it can be applied with a hose-end sprayer. If it doesn’t mention one, or gives a water volume per 100 m², use the method the label describes.

Handling concentrates safely

Even fertilisers and wetting agents can irritate skin and eyes as concentrates. Wear the gloves and eye protection the label lists while you measure and fill the jar, do it outdoors on a hard surface away from drains, and keep children and pets inside until you’ve finished. Wipe up any spills straight away and wash your hands afterwards.

Know your sprayer type

Fixed-dilution sprayers are often sold pre-filled with a product. They are set to mix at a fixed rate for that product, so you just connect the hose and go. The label says how much area one container covers, so your job is to spread it evenly over that area and no more.

Adjustable (dial) sprayers have a jar you fill with concentrate and a dial that sets how much is drawn into the water. They can be used with different products, but you need to set them correctly for each one, using the label rate and the sprayer maker’s chart.

Fixed-ratio jar sprayers draw a set proportion of whatever is in the jar. With these, you control the rate by how much concentrate you put in the jar for the area you’re treating.

Step 1: Read the label

The product label is the only source for the rate. It will say how much product to use per area, for example so many millilitres per 100 m², and how often you can apply it. For some products it also says how much water to apply it in, whether to water it in, and when not to apply it. Read the whole label before you buy, not just the front.

Write down three things before you go outside: the rate, any water volume, and whether the product needs watering in.

Step 2: Measure your lawn

You can’t apply the right amount without knowing the area. Measure the lawn in metres and use the Lawn Area Calculator, which handles rectangles, circles, triangles and odd shapes, and lets you subtract garden beds and paths. Measure the front and back separately if you treat them at different times.

Step 3: Work out how much product you need

Put the label rate and your lawn area into the Product Application Calculator. It turns “so many millilitres per 100 m²” into the amount for your lawn, and works out the water volume too if the label gives one. Measure the product with a jug, not by eye.

Step 4: Set up the sprayer

1. Check the sprayer. Look at the seals, the anti-siphon valve and the small pick-up tube inside the jar. A cracked or blocked part changes how much product is drawn.
2. Fill the jar. For a dial sprayer, add the measured concentrate and any water the sprayer’s instructions allow. For a fixed-ratio jar, add the amount for your area.
3. Set the dial to the setting that matches the label rate, using the sprayer maker’s chart. If the chart and the label use different units, convert carefully or use the calculator.
4. Connect the hose and turn the tap fully on before you start spraying. Most hose-end sprayers need full pressure to draw product correctly.

Step 5: Do a water-only trial

This is the step most people skip, and it’s the one that makes the biggest difference. Fill the jar with plain water to the same level you’ll use for the product. Then spray the lawn at your normal pace and note how far you get before the jar is empty.

• If you cover the whole lawn with a little left, you’re close.
• If it runs out halfway, walk faster or use a lower dial setting.
• If there’s a lot left, slow down or overlap a little more.

Repeat until the jar runs out just as you finish. Note your pace and the setting for next time. A few minutes of practice saves product and gives an even result.

Step 6: Spray in a pattern

• Start at the far corner and walk backwards or sideways so you’re not walking through what you’ve just sprayed.
• Do the edges first, a pass around the outside, then fill in the middle.
• Spray in parallel strips, overlapping just enough that there are no gaps.
• Keep the nozzle at a steady height and angle, and keep walking at a steady pace.
• Turn the sprayer off at the trigger or valve whenever you stop, so product doesn’t pool in one spot.
• Keep spray off paths, driveways and gutters. Anything that lands there is washed into stormwater drains by the next rain.

Weather and timing

Spray on a calm day, early or late, not in the heat of the afternoon. Wind blows fine spray onto garden beds and neighbouring yards and gives an uneven result. Hot, dry conditions can make some products scorch the leaf.

Avoid spraying just before heavy rain, which can wash product off the lawn and into drains. Larger and longer rainfall events carry more fertiliser nitrogen into stormwater, so check the forecast and follow any rain-free period on the label.

For fertilisers, the best time is when the lawn is actively growing. Feeding a dormant lawn in winter in cooler zones mostly wastes product.

Watering in

Follow the label for whether to water in, and how much. Some liquid fertilisers can sit on the leaf for a while; wetting agents usually need watering in to reach the soil. If the label doesn’t say, check the manufacturer’s product information before you water. Many hose-end sprayers have a water-only setting you can use to water in straight after.

Clean-up and storage

When you’ve finished:

1. Empty any unused concentrate back into its original container only if the label allows it. Otherwise, apply it to the lawn at the label rate or dispose of it as the label directs.
2. Rinse the jar and run clean water through the sprayer for a minute or two.
3. Let it dry with the jar off before storing it out of the sun.
4. Store the product in its original container with the label attached, locked away from children and pets.

Common mistakes

• Guessing the dial setting instead of working it out from the label rate and the sprayer maker’s chart.
• Stopping with the water still flowing, which leaves a heavy spot where you stood.
• Spraying in wind, which carries product onto paths, garden beds and the neighbours’ yard.
• Treating the whole lawn when you only need part of it. Measure the area you’re actually treating.
• Sharing a sprayer between weed killer and fertiliser. Keep a separate, labelled sprayer for herbicides.
• Skipping the water-only trial, then finding the jar empty halfway across the lawn.

Troubleshooting

Log it

Record the product, the area, the amount and the weather in your Lawn Journal. Over a season you’ll see how much you use, when the next application is due, and whether you’re close to any limit on the label for how often the product can be applied.