Gardening:" I hadn't paid much attention to the cost of producing clean water"

I love my characterful collection of vintage galvanised iron watering cans. Some of them have been in our family for years and others have been picked up second-hand. They are so beautifully balanced that carrying a couple of gallons of water is a doddle.

Plastic cans are light and cheap, but they're not as durable and lack the charm of old ones. I think a good can should be both decorative and functional.

Some new allotment site committees get a nasty surprise when they discover how much it costs to install a mains supply, so perhaps we should have a long hard look at how much water we need on the allotment. I've got used to low-energy light bulbs and not leaving appliances on standby, but I hadn't paid much attention to the cost of producing clean water. The stuff that comes out of the taps has had some pretty expensive high-energy treatment to turn it into drinking water which far exceeds the quality needed for gardens. Filling cans from rainwater collected in water butts is good enough, comes at the right temperature, and is free.

I try to avoid watering in the middle of the day when the sun is shining, to minimise water loss through evaporation. A surface mulch of composted bark, straw, or grass mowings helps keep the moisture in the ground. Unless I am watering delicate seedlings, I take off the rose and direct the water exactly where it is wanted at the roots of the plant.

David Thornton, a prize-winning vegetable exhibitor, recommends keeping

a careful eye on the weather. He reckons that if you can feel a thunderstorm brewing, it is a good idea to seize the opportunity and plant out some seedlings. When the storm breaks, the drenching and associated drop in air temperature will give them a really good start.

I was astonished to learn from the Energy Saving Trust that a hosepipe can use as much water in an hour as a family of four can in a day. A hosepipe is far from efficient at delivering water to the right places and chilly water can give young plants a nasty shock. But if using a hosepipe is too much of a summer ritual to contemplate giving up, please ditch the rotary sprayer and invest in a handheld trigger so that at least you can just water the plants that need it most.

• This article was first published in The Scotsman on April 9, 2011