Using water in the garden

Water is a precious resource. In the UK we use the same source to drink, wash our clothes and flush down the toilet. With an increasing population that source is rapidly becoming over extracted - to the detriment of our rivers, reservoirs and ground water supplies. Should we really be using it so freely to also irrigate our gardens?

Organic growers not only store rainwater where possible, using water butts, but they are also clever about how they use it. Minimising waste, and getting maximum benefit. Below is a guide on how to use water more efficiently in the garden. Follow the 6 golden rules and you too can reduce your water footprint.

  1. Build up your soil with organic matter (compost, garden waste) which will help the soil structure to retain moisture. Especially if you have light sandy soil.

  2. Target when and where the plants need it - avoid wasteful sprinkler systems. Sink thirsty plants like squashes and marrows, so water forms a puddle around them.

  3. Don't water in the heat of the day. Do water the soil, not the foliage. A good soaking every few days is better than just wetting the surface.

  4. Mulch, ie cover, the soil where possible. Bare soil loses moisture quickly through evaporation. Covering it with mulch material (straw, grass cuttings, well rotted manure, or leafmould) keeps the moisture in and weakens weeds. It also improves the soil.

  5. Water only when the plant most needs it ie critical stages like seed germination and young transplanted plants with immature root systems. Tomatoes or beans need most water when fruit or pods are setting.

  6. Lawns rarely need watering. Grass is a great drought survivor. It will come back green at the first sign of rain.

Harvesting water

Your next line of defence against drought should be to harvest as much rainwater as possible.

  • a waterbutt connected to a drainpipe is excellent. Keep it covered to prevent leaves falling in as well as it becoming a mosquito breeding ground.

  • fit butts to every available down pipe round your house, and fit guttering connected to butts onto sheds and greenhouses.


These can be one of the most water-hungry areas in the garden. Never place pots directly onto your greenhouse staging as much of the water applied to them will simply drain off. Use capillary matting or trays to capture run-off when watering and to enable plants to access this water when needed.

Seedlings are very vulnerable to ‘damping-off disease’ – a catch-all term for a variety of fungal infections that can kill an entire tray of seedlings in hours.To prevent this, only use tap water for seedlings. Once past the first potting-up stage, harvested rainwater can safely be used.

If you are planning to buy a greenhouse, get one which has rainwater gutters attached - making it easy to capture water in a butt beneath.

Reusing water

Using 'grey' water can be a good idea. If you wash up by hand, rinse soapy plates, glasses etc into a separate washing up bowl; always wash newly-picked vegetables and fruit above a bowl to collect rinsing water; maybe invest in a hand pump to collect your bathwater?

However, to use grey water from the bath or washing up, it is important to

  1. Only use water which is clear of washing up liquids and soaps. Washing liquids and powder have strong phosphates in them which are good for cleaning dirty plates, not good for the soil's microflora.
  2. Bathwater which has been stored runs the risk of incubating bacteria or other diseases and parasites. Do not store the water for any longer than it takes to cool. And only water flowers (ornamentals) with it - not crops which are eaten raw, such as salads and soft fruit.