9 things you need to know before installing a water butt in your garden

A water butt is used to store rainwater and can be any size or shape, as long as rain from a drainpipe or rain chain can flow into it. The collected water can then be used on plants and crops, as well as to top up ponds and other water features.

Free from chlorine and other chemicals found in our tap water, rainwater is a healthier choice for our plants, containing beneficial nitrates and other organic matter.

If you want to get ahead of the next hosepipe ban by adding a water butt to your garden, we've explained everything you need to know about this eco-friendly garden update below.

Tips for using a water butt in your garden

1. Water butts typically attach to downpipes running from gutters and are fed by a diverter that syphons water from the downpipe into the butt. Once full, the rainwater coming off the roof simply continues into the drain.
2. Ideally, position a water butt where you most need water, such as next to your vegetable garden, or near the house for easy access when watering houseplants.
3. Site the rain barrel in the shade if possible. Keeping it cool will reduce the chance of bacteria flourishing.
4. Raise your water butt off the ground so you can use the tap at the bottom and fit a watering can underneath. If the butt does not come with a stand, create a base to stand it on using an even stack of bricks.
5. Make sure your water butt has a lid to stop debris falling in and to prevent flies and mosquitoes laying eggs in the water.
6. Try making a filter to cover the inlet to the rain barrel and prevent leaves and other debris contaminating your stored water.
7. Water butts come in a range of different sizes and there will be one to fit the space you have available in your garden landscaping. You can also join several together if you have a large garden.
8. Water butts are easy to install and widely available online and from DIY stores. Installation kits include the barrel, a diverter and a tap for filling a watering can.
9. Don't forget about your lovely supply of fresh rainwater. Using the water frequently helps to dilute stored water with fresh water to help keep the water clean.

Water butt shopping picks

Why do you need a water butt in your garden?

"Gardeners are having to be smart about how they water their gardens by investing in a water butt," says Mark Gush, Head of Environmental Horticulture at the RHS. "Thinking ahead is one of the best things we can do in preparing our green spaces for weather extremes, ensuring that even during the height of summer they provide a green oasis."

Gardening journalist Ruth Hayes agrees on the importance of water butts. She has five (yes five!) situated around her garden.

"Water butts are an essential piece of gardening equipment because harvested rainwater is better for plants than tap water, and of course once you’ve got your butt installed, collecting water is free and saves money as part of your garden water saving," she says.

"Mine are attached to downpipes from the house, the greenhouse and the shed, which makes it so much easier to transport water to exactly where it's needed, and between them they hold a whopping 800 litres of water when full."

What's the best design for a water butt?

There are plenty of widely available options to choose from including smart designer styles. The most common variety of water butt tends to be those made of green plastic with a black lid.

However, there are a variety of other designs and shapes available, including ones that are beehive-shaped or slimline, as well as a variety of materials such as clay, wood or terracotta (like this one from Amazon). So whether you have a cottage garden or a more modern garden, you'll be able to find a design to suit your space.

You can also buy water butts with integrated planters, as well as slimline models for slotting into narrow spaces as part of your small garden ideas. You can, of course, also have a go at making your own if you're looking for a budget garden idea and are up for an easy DIY project.

How do you keep the water in a water butt fresh?

"There are a number of steps you can take to ensure the water in your water butt or rain barrel stays fresh for as long as possible," says Hozelock's Sarah Dixon.

"First, keep the butt or barrel out of the sunlight as much as possible, otherwise algae and bacteria will start to form. It is also important to keep the top covered, as this will prevent any debris from getting inside and contaminating the water.

"There are also a number of treatments available, such as Hozelock's Water Butt Treatment (available on Amazon), which have been formulated to treat stored water by preventing unpleasant odours and keeping it free from slime and algae."

What are the problems with water butts?

Water butts are easy to use and pretty much problem-free. But one thing to remember is that it's important to keep downpipes and gutters clear of leaves, moss and any other debris, especially in the autumn, as they will block water getting into your barrel and also increase the risk of contamination.

"It's important to keep your water butt covered with a secure lid," says the experts at Envii. "Mosquitoes don’t like moving water, which means the still water in rain barrels is the perfect breeding ground for them. A secure, fastened lid will help to keep them out.

"If mosquitoes do make their way into your rain barrel, mix a small amount of olive oil with water and spray over the top of the stagnant water. This will create a film over the surface of the water and kill off the mosquito larvae."

How often do you need to clean a water butt?

When it comes to how often to clean a rain barrel, the expert advice is pretty consistent. "I advise cleaning your rain barrel annually," says Ruth Hayes, "either by disconnecting it and giving it a scrub or, more easily, by using a treatment that you can drop straight into the barrel."

The experts at Envii agree that once a year is the way to go. "Autumn is the best time to do it. Clean the outside of the butt using a garden hose to remove grime and stains. Scrub the interior to remove algae and sludge that builds up around the sides.

"Avoid using cleaning products as these can leach into the water and contaminate your soil when watering plants. Instead, use warm water with a mild washing-up detergent, avoiding the use of antibacterial detergents."

By following these expert tips, you'll be able to make the most of your water butt – saving money on your bills and lowering your carbon emissions while giving your plants healthier water.

For more garden advice, read our guide on the best time to water your plants or learn what drip irrigation systems are.