Drought-proof, low maintenance perennials include any with grey or silver leaves, succulents such as stonecrops, and some herbs. All make the best of any well-drained soil.
‘Moonshine’ yarrow (Achillea ‘Moonshine’, Zone 3) Growing 60 centimetres tall and wide, it looks like a silver-leafed fern with the bonus of flat, lemon yellow flowerheads in June and July. Snip faded flowers; the foliage gleams on into October. A fine plant to hide the bare stems of taller black-eyed Susans, shasta daisies, sneezeweed (Helenium) or false sunflowers (Heliopsis).
Daylilies (Hemerocallis cvs., Zone 2) Always dependable and colourful. A mulched bed of daylilies will take care of itself in sun or light shade for many years. This is one plant you don’t even need to cut back in fall. Choose early, mid-season and late bloomers for continuous colour from June to September. Daylilies grow to between 45 centimetres and one metre tall with a spread of between 30 and 90 centimetres. Clumps of the native Culver’s root (Veronicastrum virginicum) set among them add the vertical contrast of slender 1.4-metre-tall spires of tiny, white flowers.
Japanese silver grass (Miscanthus cvs., Zone 5) Tall, graceful, dependable and non-invasive, these grasses sway in the summer breeze at the back of beds. Pick among dozens of cultivars with green, silvery, striped or gold-banded foliage from 80 centimetres to three metres tall, and plant on 60-centimetre centres; grass will spread to between 75 centimetres and 1.2 metres to achieve a visibly full effect.
Hardy herbs Left to their own devices, with just a bit of tidy-up spring pruning, both winter savoury (Satureja montana, Zone 5) and common sage (Salvia officinalis, Zones 4 to 6) grow into wide, sturdy, fragrant bushes (30 centimetres or more tall and wide) for edging hot, sunny beds.
Stonecrop (Sedum spp. and cvs.) Besides September-flowering Autumn Joy (‘Herbstfreude’, Zone 2), newer summer stonecrops, all around 50 centimetres tall, include bright pink ‘Neon’ (Zone 2); ‘Matrona’, with pink-edged, grey-green leaves (Zone 3); dark-leafed ‘Purple Emperor’ (Zone 2); the unusual cream-flowered ‘Hab Gray’ (Zone 4); and the pretty pink-and-white ‘Strawberries and Cream’ (Zone 3). Planted on 30-centimetre centres, these self-sufficient succulents knit together and add contrasting leaf textures and colour to a cottage garden.