A courtyard is perfect for herbs

Small British courtyards have a great deal going for them where herbs are concerned. Walled on three sides, they hold warmth well into the evening, shelter tender leaves from wind, and sit within a few steps of the kitchen door — which matters more than most gardeners admit. The herbs you actually use are the herbs you can reach in the rain while the kettle boils.

The catch is that courtyards are also rain shadows. A high wall or hedge can halve the rainfall that reaches your pots, and paving reflects heat back onto foliage on a July afternoon. Add the fact that containers dry out far faster than open ground, and watering becomes the single most important skill you will learn. Get that right and a courtyard the size of a dining table will keep you in fresh herbs from May to October.

Rosemary, mint and thyme: three that earn their keep

If space is tight, these three cover most of what a British kitchen asks for. Rosemary for roasts and lamb, thyme for soups and stuffings, mint for new potatoes, peas and summer drinks.

• Rosemary is a Mediterranean shrub and detests sitting wet. Give it the sunniest spot you have, a gritty compost, and a pot at least 30cm across so it has room to develop a proper root system. Upright varieties grow tall and narrow, which suits a corner; prostrate ones will trail over a low wall. Never let it stand in a saucer of water over winter.
• Mint is the opposite character: it likes moisture and will romp away given half a chance. Always grow it in its own pot, never sharing with anything else, or its runners will strangle the neighbours within a season. A 30cm pot is fine, and it will tolerate a little shade.
• Thyme wants sharp drainage above all else. Mix plenty of horticultural grit into the compost and top the pot with a layer of gravel so the base of the stems never rests on damp soil. Common thyme and lemon thyme are both reliable; creeping thyme will soften the edge of a pot or a step.

If you have room for a fourth, flat-leaved parsley and chives cope well with slightly richer compost and partial shade, and both are cut-and-come-again crops.

Containers, compost and drainage

Terracotta looks handsome and its porous walls help prevent waterlogging, but it dries out quickly — a real consideration in a sun-trap courtyard. Glazed pots hold moisture longer. Whichever you choose, size matters: a generous pot stays cooler, dries more slowly and supports a bigger, longer-lived plant than a cramped one.

Use a soil-based compost such as John Innes No. 2 for rosemary and thyme, which prefer something leaner and more stable than a rich peat-free multipurpose. Mint is happy in multipurpose. Put a layer of broken crocks or gravel in the base, stand the pot on feet so water drains freely, and raise them slightly on tiles if your courtyard floods in winter. Good drainage is not a detail here; it is the difference between a plant that survives the winter and one that rots.

Watering wisely

In summer, courtyard pots may need water every day, sometimes twice on a blistering afternoon. Water in the morning where you can, directing the flow at the compost rather than the leaves, and soak until it runs from the base. A quick daily splash does more harm than good, encouraging shallow roots that fail in a heatwave.

Check before you pour. Push a finger two or three centimetres into the compost; if it is damp, wait. Rosemary and thyme would rather be slightly dry than constantly moist, so let them approach dryness between waterings. Mint is thirstier and will sulk visibly, with limp leaves, if left too long. In winter, cut right back — once a fortnight is usually plenty, and remove saucers so pots never stand in cold water.

Harvest regularly, and harvest properly

Regular picking is what keeps herbs bushy rather than leggy. Use sharp scissors and cut just above a pair of leaves, which encourages two new shoots from that point.

• Take no more than a third of the foliage at any one time.
• Pinch out the growing tips of mint and thyme every couple of weeks through summer.
• Never cut rosemary back into old, leafless wood — it rarely regrows. Take sprigs from the soft green tips instead.
• After mint flowers, cut the whole plant back by half to force a flush of fresh, tender leaves.
• Shear thyme lightly after flowering to keep it compact and stop it going woody.

Pick in the morning, after the dew has dried but before the sun is high, when the oils are at their most concentrated.

Keeping the season going

A light feed every fortnight through summer suits mint, parsley and chives; rosemary and thyme need little or nothing. Watch for aphids on soft mint tips — a firm spray with water usually deals with them — and keep an eye out for vine weevil grubs in pots, which hollow out roots over winter.

As autumn arrives, move pots against a sheltered wall, reduce watering and stop feeding. Rosemary and thyme are hardy but hate wet feet, so raise pots onto bricks. Take semi-ripe cuttings of rosemary in late summer and root them in gritty compost on a windowsill, and pot up a few mint runners in autumn. Come spring you will have replacements ready, and a courtyard that smells of the Mediterranean before breakfast.