How to cope with drought 

1. The best and most successful way of coping with drought is to use drought-tolerant plants. The following characteristics are usually good indicators that a plant is able to grow (and in many cases thrive) in droughty conditions:

a) Plants with thick or waxy leaves, or those which have leaf hairs which makes them
  look grey, or those which have silvery leaves – these reduce evaporation through the
  leaves eg. Sedum, Phlomis, Convolvulus cneorum.
b) Plants with narrow leaves or a hummocky shape - these reduce the surface area of
  the leaf, so there is less evaporation, eg lavender, rosemary, Genista hispanica
c) Plants with long tap roots to reach any moisture deep in the soil eg evening
  primrose.
d) Bulbs which are dormant in summer – these tolerate the dry summer period by
  being dormant during that time.

2. When planting out, small plants cope better with drought than larger specimens.

3. Shelter plants from wind and create shade to reduce evaporation.

4. Add plenty of organic matter to the planting hole. Use home made compost, mushroom compos or well-rotted manure.

5. Water well after planting and mulch the area around the plant to stop the moisture evaporating. Semi-permeable membranes or geotextiles can also be used to reduce evaporation from the soil.
 
Mulches include organic matter, such as home made compost, mushroom compost, well-rotted manure, wood chippings, leafmould and cocoa shells.It is vital to make sure that the soil is well watered before laying the mulch, which should be at least 5cm (2in) deep.

Alternatively, gravel is an excellent material for mulching plants. Plants love it – it conserves moisture, retains warmth and keeps plants dry in winter, and it helps to suppress weeds, so reducing maintenance.

6. Remember that new plantings need to be watered until established. Autumn/winter plantings require less watering than spring and summer plantings, except in very dry spells.

7. Raising the height of mower blades reduces water loss from lawn areas.

8. Buy a water butt to collect rainwater from the roofs of the house, garage, shed or greenhouse.

9. Waste water from the house can be used to water plants but do take care not to use anything with bleach or disinfectant.

Some drought-tolerant plants:

Alchemilla mollis
Anaphalis triplinervis
Artemisia absinthium 'Powis Castle'
Ballota pseudodictamnus
Brachyglottis monroi
Buddleja crispa
Cistus
Convolvulus cneorum
Coronilla valentina ssp. glauca
Centranthus ruber
Cerastium tomentosum
Cynara cardunculus
Dianthus
Echinops
Elaeagnus x ebbingei
Eryngium

Remember that plants can only be drought-resistant once they are established, so will
need watering when first planted.

Design ideas for drought-tolerant plantings - Create a Mediterranean garden

Mediterranean gardens are excellent for coping with drought and work especially well in hot, sunny and dry situations..

Real Mediterranean gardens are often rustic and unpretentious, with cobbles or randomly laid paving, white-washed or natural stone walls, and simple rustic pergolas. More sophisticated gardens have glazed tiles, mosaics, or terracotta paving, intricate pebblework, and water features.

Shade is seen as an essential, for humans and plants, and they create a cool and inviting look. Trees are ideal for creating shade and throw interesting shadows. Simple, rustic pergolas provide shade too, especially if covered in plants such as Jasmine, Wisteria or fruiting vines.

Generally speaking, use bold, architectural and colourful plants. Hot colours work well in strong sunlight, creating an exotic feel, and are especially good in pots. Pots can require a lot of watering, so choose drought-tolerant plants such as Pelargoniums. In borders, evergreen foliage plants, silver leaves and white flowers help to create that cool atmosphere.

The scents of fragrant flowers and foliage, which release their scent in the sun, capture the smell and mood of the Mediterranean. Species, such as rosemary, cistus, lavenders, artemisia are particularly apt.

Mediterranean plants are naturally adapted to live in well-drained soil and hot, sunny situations. They often grow near the sea and have to tolerate salt. Many, like the Jerusalem Sage, Phlomis fruticosa, have hairy or wooly leaves which protect against salt and evaporation, and look grey. Others, such as Artemisia or Helichrysum have silver leaves. Others may have small leaves with a small leaf surface area; such as lavender and rosemary, or have tough leathery or shiny leaves, such as bay and laurel.

Suitable plants include palms, such as Trachycarpus fortunei, Phoenix canariensis and Chamaerops humilis. Architectural plants, such as Yucca, Cordyline, Cannas and Agave, look suitably exotic. Pencil cypresses, olive trees, fruiting vines, figs, and herbs, such as basil, capture the mood, while Cistus, sages, rosemary, lavender, jasmine and curry plants (Helichrysum) add the right aroma.

A water feature creates a cooling effect and need not use a lot of water, as long as a self-contained system is used. Small and unassuming wall-mounted water features bring the gentle sound of water, while large Cretan pots brimming with water are more dramatic. Tanks of water are also common.

Lighting can greatly enhance the garden at night, but should be used simply and sensitively.