Though drought is a serious threat to every London garden, ditching the hosepipe will encourage us to use water wisely. None will be wasted when the watering can's spout is directed at the roots of a plant, where it is needed, whereas a hose sprinkles water over the top wastefully.
"Grow plants mean, keep them keen" is the new mantra — be sparing with water and you will find they will grow more robustly, and be more resilient. Too bad you have to switch off the trickling fountain, but you can use tinkling windchimes instead to give your garden traffic-distracting "white" noise.
There is much we can do to conserve water. Install at least one water butt, fixing to a downpipe so every drop of rainwater is used (B&Q's YouTube channel shows you how). Collect "grey" water from household sources including bath, kettle and cooking water to use in the garden, but not on food crops. Let the lawn grow: it will send down deeper roots and look a lot better than if it had a twice-weekly scalping.
Improve the soil structure where you can by adding well-rotted compost or organic matter that will hold more water. When you plant trees and shrubs, dig in plenty of compost to help retain water, and cover with a thick mulch that will do the same. In containers, use a special water-retaining compost (New Horizon make a good organic one), and top-dress all pots with gravel to reduce evaporation.
In RHS The Garden magazine, plants-woman Beth Chatto, who created a glorious drought-proof garden in Essex where the annual rainfall is a scant 20 inches, advises replacing thirsty plants such as delphiniums, asters and many bedding plants with tougher perennials. Provide good drainage so plants don't sit in wet over winter, and you can grow Chatto stalwarts such as euphorbia, sedum, alliums, catmint, broom, lavender, eryngium and echinops. Her bread-and-butter plants for dry shade areas are Epimedium versicolor and Helleborus foetidus, which flowers for months.
For this summer's containers, bypass petunias and busy lizzies for pelargoniums, osteospermum, gazanias, verbena, lantana, festuca grass and cordyline, growing them in groups in large pots; small pots dry out much quicker. Bulbs such as lilies and eucomis need little water.
Water-storing succulents need even less and can masquerade as houseplants in winter. Sempervivum rosettes look striking in bowls on the patio table, can stay out all year and never need watering.
Which vegetables are drought-resistant? Chard, chives, carrots as well as aubergines, tomatoes and peppers. Small outdoor cucumbers but not courgettes; spinach, but not lettuce. The drought-proof potato to go for is Sarpo Mira.
Matthew Wilson, MD of Clifton Nurseries, designed a "zero-irrigation" garden at RHS Hyde Hall in 2001 that has never been watered, and his tested tips for London gardeners include creating a dam around the base of plants to ensure water reaches the roots rather than rolls off a dry surface, removing weeds that compete for water and avoiding digging as this exposes water, allowing it to evaporate.
From April 2012, shoppers at Clifton Nurseries can expect to find an increase in water-conserving products such as new types of water butts and drip-feed systems. There will also be a wide range of Wilson's recommended drought-busting plants such as hebe, cistus, sage and santolina as well as climbers campsis, passiflora and solanum. Mediterranean plants with silver and grey foliage will take centre stage and olive will be the tree of choice.
Other London garden centres take note — we need to change our gardens as well as our watering habits.
Pictures by: GAP photos