Why a Courtyard Border Is Different

A courtyard is a lovely thing to have, and a tricky thing to plant. Walled on two or three sides, it soaks up heat during the day and releases it slowly after dusk, which means the border tucked against the brickwork sits in its own little microclimate — often a full hardiness zone warmer than the open garden beyond the gate. Frost arrives later and leaves earlier, so tender shrubs that sulk elsewhere can thrive here. The catch is rain: walls and paving create a rain shadow, and a border beneath an overhanging eave or beside a fence may see a fraction of the water that falls on the lawn. Add reflected light from pale paving and the space can become surprisingly intense in midsummer.

The good news is that these conditions suit a generous palette of plants. Choose hardy shrubs, ornamental grasses and drought-tolerant perennials, plant them well, and mulch every spring, and you will have a border that looks after itself for years.

Start with the Soil and the Bones

Before you buy a single plant, dig over the border to a spade's depth and fork in two or three buckets of well-rotted manure or garden compost per square metre. Courtyard soil is often compacted from building work, and it drains sluggishly against a wall. If yours is heavy clay, add grit as well; if it is thin and gritty, the compost is doing double duty by holding moisture.

Then set out the evergreen structure — the shrubs that will hold the border together in January. In a small space, aim for three or four, spaced so they have room to reach their natural shape without constant clipping:

• Choisya ternata — glossy evergreen leaves and fragrant white flowers in late spring, plus a second flush in autumn. Happy in sun or light shade.
• Pittosporum tenuifolium — neat, dark stems and small wavy leaves. Responds well to a light trim in mid-spring if it outgrows its corner.
• Euonymus fortunei — a workhorse for shade, with variegated forms that lift a gloomy wall.
• Rosemary — superb on a hot, sheltered south-facing wall, where it will scent the whole courtyard and shrug off drought.
• Skimmia japonica — for a north-facing corner, with red buds through winter and fragrant flowers in spring.

Leave a gap of at least 30cm between the mature foliage and the wall itself. Air moving behind a shrub is what keeps fungal problems at bay.

Grasses for Movement and Light

In a confined space, ornamental grasses earn their place twice over: they soften hard lines, catch the low evening sun, and rustle in the slightest breeze, so the courtyard never feels static. Most are drought-tolerant once established and need nothing more than a haircut in late winter.

• Stipa tenuissima — feathery, tactile, and utterly undemanding. Cut back hard in March.
• Miscanthus sinensis — taller and architectural; the smaller cultivars suit a courtyard better than the giants.
• Hakonechloa macra — a cascading, shade-tolerant grass that looks superb spilling over paving.
• Anemanthele lessoniana — pheasant's tail grass, evergreen in mild areas, with orange-flushed blades all winter.

Plant grasses in loose groups of three rather than singly; repetition is what makes a small border read as designed rather than accidental.

Perennials That Forgive a Missed Watering

Drought-tolerant perennials are the colour engine of this border, and the list is longer than most people expect. Plant them in late spring once the soil has warmed, and water them through their first summer only — after that, they should be on their own.

• Salvia nemorosa — deep purple spikes from June to August, and again if you deadhead. Bees adore it.
• Nepeta — catmint, billowing and grey-leaved, wonderful at the front edge of paving.
• Verbena bonariensis — see-through stems that never crowd a small space; self-seeds gently.
• Echinacea — robust daisies that hold their shape well into autumn and feed the birds.
• Sedum spectabile — succulent foliage topped with flat pink flowerheads that butterflies queue up for.
• Geranium 'Rozanne' — a sprawling, long-flowering cranesbill for slightly shadier corners.

Aim for roughly a third evergreen shrubs, a third grasses, and a third flowering perennials, then resist the urge to fill every gap. Courtyard borders need airflow more than they need abundance.

The Spring Mulch and a Simple Year of Care

Mulching is the single habit that makes this border genuinely low-maintenance. Each spring, once the soil has warmed but before the weeds get going — late March into April is ideal — spread a 5cm layer of well-rotted bark or composted green waste over the whole border, keeping it clear of stems and crowns. This locks moisture into the soil, suppresses annual weeds almost entirely, and feeds the worms that do your cultivating for you.

Beyond that, the calendar is short. Cut back the grasses and any tatty perennial foliage in late February or early March, before new shoots appear. Deadhead the repeat flowerers through summer if you have the time and the inclination. Give the shrubs a light trim after flowering if they are outgrowing their corner, but never a hard prune into old wood. Water deeply rather than little and often in the first year, and after that only during a genuine drought. In a sheltered courtyard, slugs can be persistent in spring — a few beer traps or a nightly torchlit patrol will usually keep on top of them without chemicals.

Planting for Winter, When the Courtyard Is Most Seen

Here is the thing about a courtyard: you look at it from indoors, through glass, for much of the year. So it must earn its keep in November as much as June. Include at least one shrub with scented winter flowers — Viburnum bodnantense or Sarcococca confusa — and let a couple of hellebores settle in beneath them. Add a small evergreen fern such as Polystichum for texture when everything else has collapsed. Their dark, glossy leaves and quiet flowers will carry the border through to spring, and the mulch you laid in April will have done most of the work of getting them there.