Choosing Drought-Tolerant Plants for a Dry Garden

Why a dry garden is a garden, not a compromise

Many of us now spend the summer watching the forecast, waiting for rain that never quite arrives. Rather than fighting a hot, free-draining border with endless watering cans, it makes far more sense to plant things that actively enjoy those conditions. A dry garden can be every bit as lush, scented and full of life as any damp-loving scheme — it simply asks you to choose your plants more thoughtfully. Once established, most of the plants below will sail through a hot July and August on little more than the occasional soak.

The trick is to match the plant to the place. A south-facing border at the foot of a wall, a raised bed over chalk, or a gravel garden in full sun will always be thirsty ground. Work with that, rather than against it, and you will spend your weekends sitting in the garden instead of dragging a hose around it.

Silver leaves and aromatic herbs: the backbone of a dry border

Silver, grey and woolly foliage is nature's way of coping with heat. Those pale, often hairy leaves reflect strong sunlight and lose far less moisture than soft green ones, and many of the plants that carry them are also beautifully scented.

• Lavender — Lavandula angustifolia and its many cultivars give you colour, scent and structure. Trim lightly after flowering, never into old wood.
• Rosemary — upright forms make a fine low hedge; prostrate ones will spill over a wall or gravel edge.
• Thyme — creeping and bush varieties both work well between paving stones and along border fronts.
• Purple sage and common sage — handsome grey-green or purple-grey leaves with a rich herbal scent.
• Cotton lavender — Santolina makes a neat, finely cut silver mound that responds well to a hard clip each spring.
• Origanum and Dianthus — marjoram and pinks bring late-summer flowers and nectar for bees.

Plant these in generous drifts rather than one of each. Repetition is what gives a dry border its calm, designed feel.

Mediterranean shrubs for structure and scent

Shrubs hold a dry border together through the seasons, giving height and mass where perennials come and go. Choose evergreens and sub-shrubs from the Mediterranean and you will get year-round presence with almost no watering once the roots are down.

Rock roses (Cistus) are the essence of a hot, sunny bank, flowering their hearts out in early summer in white, pink or crimson. Jerusalem sage (Phlomis fruticosa) offers grey leaves and whorls of soft yellow flowers, and looks superb against gravel. Russian sage provides a haze of blue from midsummer into autumn, while Caryopteris picks up the baton with powder-blue flowers into September.

If you have room, a fig or a myrtle adds a distinctly southern air, and a mophead-free shrub such as Buddleja will reward you with scent and butterflies. Space shrubs generously — crowded plants compete for water and suffer far more in a dry summer.

Deep-rooted perennials that find their own water

Perennials with long taproots and fleshy storage roots can reach moisture far below the surface, which is why they shrug off drought so well.

• Sea holly (Eryngium) — metallic blue flower heads above deeply divided leaves; superb in gravel.
• Globe thistle (Echinops) — architectural, bee-magnetising and utterly unfussy about poor soil.
• Verbascum — tall spires of yellow, white or pink, thriving on dry, chalky ground.
• Bear's breeches (Acanthus) — bold, sculptural foliage that anchors the middle of a border.
• Red valerian and Limonium — self-seeding stalwarts of walls and sunny edges.
• Kniphofia and Agapanthus — bold, exotic-looking flowers that relish a baking summer.

Add bulbs for extra value: alliums, tulips, crocus and nerines all flower brilliantly before or after the main season and need no watering at all.

Planting, mulching and the first two summers

Even drought-tolerant plants need help while they establish. Autumn planting is ideal, giving roots time to settle before the heat arrives. Improve heavy soil with coarse grit rather than rich compost, because most Mediterranean plants resent sitting in damp, fertile ground. Add a 5–8cm layer of gravel or grit mulch around each plant, keeping it clear of the stems — this suppresses weeds and dramatically reduces evaporation from the soil surface.

Water thoroughly for the first two summers, then begin to withdraw. By the third year, most plants will be entirely self-sufficient. Resist the urge to feed; lean, poor soil keeps plants compact, floriferous and long-lived, whereas rich feeding produces soft, floppy growth that struggles in a dry spell.

Pulling it together for year-round interest

Think of the border as a painting. Use silver and grey foliage as your base layer, thread it through with blues, yellows and soft pinks, and repeat two or three key plants to unify the whole. Grasses such as blue fescue and Stipa add movement and catch the low evening light beautifully.

Finally, leave seedheads standing through winter. Eryngium, Echinops and Phlomis all hold their shape in frost, feeding birds and giving the garden structure long after the flowers have gone. A dry garden is never bare — it simply changes character with the seasons, and asks very little of you in return.