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In the garden

Water Efficiency


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In the garden

In a hot spell, garden watering can account for as much as 70% of the water we use. There are 5 ways you can use water more efficiently in your garden:

  1. Save water
  2. Watering tools
  3. Water wisely!

Save water

Water is the earth's most precious resource. Like all living things, plants need it to survive. Fortunately watering wisely – in the right amounts and in the right places – will keep your garden healthy while minimising waste.

When to water

It's best not to water as a matter of routine. Only water plants when they show signs of needing a drink or if they are newly planted. If a border really does need watering then it should be done either early morning or preferably late evening; this minimises the water lost to evaporation and prevents scorching. When you do water, it is vital that the plants are given a thorough drenching, or else you will simply moisten the top few centimetres of soil and the roots will grow upwards in search of it. This creates a vicious circle: shallow-rooted plants require regular watering, whereas deep-rooted ones are capable of seeking out their own supply further down. Mulching beds will also greatly reduce the watering requirements as it seals in moisture, preventing evaporation.

How much to water

The amount of water plants need varies widely: those that thrive in full sun and free-draining soil require very little; large-leaved, luscious ones a great deal more. When first planted they all need a good soak; after that will depend upon plant and weather. Plants put in the ground in autumn will require no further watering unless the weather is unusually dry; by the time summer comes around their roots will be more than adequate to draw in water from the ground in all but the driest of weather. Plants put in either in spring or early summer will need watering throughout their first summer.

To water or not to water

New lawns require watering throughout their first season. But established lawns will survive dry summers perfectly well without watering, unless there are extreme drought conditions – at which point there will be a hose-pipe ban, anyway. In a long hot summer lawns will go brown, but when cooler, damper weather arrives they will begin to recover.

Watering a lawn takes copious amounts of water. In dry periods, once you've started you will have to continue, because the lush new growth triggered by watering will need further amounts of water to maintain it.

If you really must water, then make sure you do it either early in the morning or later in the evening – never in between, or the grass will scorch in the sun. Better still, connect a timing device to a sprinkler, set to come on during the night, when every drop of water will be absorbed by the grass instead of evaporating in the daytime heat.

Conserving water

As recent hot summers have proven, water is not the infinite resource we once presumed it to be. Conserving the water we have and using it wisely within a garden makes sense on many levels. It will reduce costs if you have a water meter. You can also collect your own – not only is this free to do, but it's better for the environment.

Grey water

Much of the waste water you produce at home can safely be used in the garden. This kind of domestic waste water is called grey water – completely different from black water, which is sewage. Every home produces large quantities of grey water, which is fine for plants as long as it is not contaminated by an excess of detergents, soaps or cooking residues.

  • Never use grey water that contains bleach, disinfectants or strong cleaning products
  • Don't use grey water on edible plants or for filling ponds
  • Alternate the use of grey water with rain- or mains water
  • Never use grey water on container-grown, newly propagated, or conservatory or greenhouse-grown plants

Mulch bare soil

Mulching can slow evaporation from bare soil whilst still allowing rainwater to pass through to plant roots. Apply a 50mm (2") layer on top of moist soil. A water permeable membrane can also be used with the mulch to save water and control weeds.

FSC® certified bark chips are a good choice as they are taken from well managed forests, helping to conserve nature.

Mulches, Sand & Bark

Improve the soil quality so that it can retain more moisture

Adding a soil conditioner can help to retain more moisture in a light chalky or sandy soil. It can also help to improve drainage in a heavy clay soil.

Home made garden compost makes a good soil conditioner – and has the additional benefit of helping to reduce the amount of kitchen and garden waste that your household sends to landfill.

Peat free soil improver is another option as is manure.

Composters

Fertilisers

Choose plants that require less water

Hebes, lavenders, thymes and alyssums are examples of plants that do not require much watering once established – and they can all help to support British wildlife.

Drought resistant lawn seed can help to establish a lawn that requires less water. Setting your lawnmower so that grass is allowed to be longer in summer can help the lawn to retain moisture.

Plants, Bulbs & Seeds

Watering tools

If you can manage it, watering with a hose or watering can is best – this way you can keep a close eye on your plants, not only to see if they're thirsty but also to check for any problems such as pests or diseases. However, many people simply don't have the time for this. If that sounds like you, then consider a sprinkler, soaker hose or other automatic watering system.

Hoses

A good garden hose will last season after season if stored carefully. Make sure the hose pipe is long enough to reach the areas you need to water. A long-reach watering wand will be handy for delivering water to hanging baskets and pots. For even more control when applying water, use a trigger pistol or multi-function gun, which provide a selection of spray patterns. Hose guides protect plants from damage by guiding the hose around obstructions as you unwind it.

Hoses

Watering cans

A traditional and effective way to water plants on a small scale is with a watering can. New designs, which include angled rose attachments, help prevent spilling when full and enable more accurate watering.

Watering cans

Effort-free watering

Sprinklers are useful for covering lawns or watering newly planted beds; traditional ones spray in a circular pattern, while newer models can be set to spray in a specific shape to suit your garden. Oscillating sprinklers rotate from side to side to cover a wider area. Some models have a choice of spray patterns: a standard spray suits established lawns and borders, while a mist spray is for newly seeded lawns. For delivering water exactly when and where it's needed, an automatic watering system is ideal. It can be fitted with a timer that will switch your water source on and off at specified times – great for when you're out or on holiday. In-line feeders make it possible to feed and water your plants at the same time. The majority of water companies in England and Wales now require customers who use sprinklers or any unattended garden watering device to have a water meter installed. Contact your water supplier for details.

Sprinklers

Automatic watering systems

A good watering system will deliver water only to the plants that need it and at the most appropriate time. Normal sprinklers, though popular, tend to waste water as they often miss their target. Soaker hose or dripper systems are much more accurate ways of applying water as they deliver it exactly where you want them to. They are easy to install and, once fitted, will save you hours of time and effort. What's more, you can control the flow manually or with the help of a timer.

A soaker hose watering system is made up of a porous hose that allows water to seep out all the way along its length. Once connected to a tap and woven in between plants as needed, the hose can be hidden under a few centimetres of soil or mulch. This system is best for raising moisture levels over a large area such as a border or bed.

A dripper system waters each plant or container using tiny water outlets or drippers connected to a supply hose. It can be assembled to fit any garden layout and is ideal for pots and hanging baskets as well as flowerbeds.

Irrigation systems

Collection & storage

You can do a favour to your plants, the environment and even your wallet by collecting, storing and recycling rainwater. Not only is rainwater free, but it is better for plants than tap water as it contains more nutrients. What's more, unlike hard mains water, rainwater will not leave limescale deposits or increase the alkalinity of the soil. The best way to collect rainwater is in a water butt connected to a downpipe.

Watch our 'How to...' install a water butt video Opens link in new window

View our 'How to...' install a water butt guide

Water butts & accessories

Water wisely!

Switch to using a watering can instead of a sprinkler. You can then target the water accurately to where it is needed – at the plants' roots.

Water plants in the evening so that they can make use of it overnight, otherwise some will simply evaporate before the plants can use it.

Micro irrigation is an efficient way to keep containers watered without wasting water.