A border you can smell before you see it

There is a quiet luxury in stepping out of the back door and brushing past a cloud of rosemary and lavender. A fragrant herb border in pots gives you that small ceremony every time you put the bins out or head for the car. It is also deeply practical: herbs grown close to the kitchen are used more often, cut fresher, and far less likely to be forgotten at the back of the veg patch. The trick is to treat the group as a border, not a random collection of pots — a considered arrangement of height, texture and scent that works in a space as small as a doorstep.

Find the sunniest spot you have

Rosemary, thyme and lavender all hail from the Mediterranean, and they will only reward you with dense, aromatic growth if they get light. Aim for at least six hours of direct sun in summer, which in most UK gardens means a south or south-west facing wall. A spot beside a door is ideal, provided it is not directly beneath a roof drip or a downpipe — soggy roots in winter will finish off lavender faster than any frost.

Shelter matters as much as sun. A corner that catches the wind will dry out compost quickly and snap brittle rosemary stems. If your only option is exposed, group the pots tightly together so they shield one another, and stand them on feet or bricks so excess water drains away from the base rather than pooling underneath.

Pots, compost and the drainage question

Size matters more than style here. A rosemary or lavender needs a pot of at least 30–35cm across to develop a decent root system; thyme will manage in something half that. Terracotta is a good choice because it breathes, though it dries out faster in a hot spell — glazed pots hold moisture longer but need generous drainage holes.

For compost, mix your own free-draining blend:

• Two parts peat-free multipurpose compost for body and moisture retention.
• One part horticultural grit to open up the structure.
• A handful of bark fines per pot, which keeps the mix airy and stops it slumping.
• A layer of crocks or gravel at the base, never a solid seal.

Resist the temptation to add rich manure or heavy feeding. Poor, lean conditions concentrate the essential oils that give these herbs their scent. Fat, pampered plants look lush and smell of very little.

Planting the four together — with one exception

Rosemary, thyme and lavender make happy neighbours. They want the same things: sun, sharp drainage, and a light trim once a year. Choose a compact lavender such as 'Hidcote' or 'Munstead' rather than a sprawling variety, and an upright rosemary if space is tight. Thyme works beautifully along the front edge of the group, where its creeping habit softens the rims of the pots.

Mint is the awkward one. It likes moisture, tolerates a little shade, and spreads with alarming enthusiasm through any compost it can reach. Give it its own container — a 30cm pot is plenty — and keep it slightly apart from the others so you can water it more freely. Sink the pot into the group for the look, but never plant mint directly into a shared container, or it will shoulder everything else aside within a season.

Watering, feeding and the annual chop

For the first summer, water regularly — small pots in full sun can need a drink every day in July. After that, let the top couple of centimetres dry out between waterings; lavender in particular resents constant damp. Feed sparingly, perhaps once a month with a weak liquid feed, and only for mint and thyme. Overfed rosemary grows soft and leggy.

Pruning is where most people go wrong. Trim lavender in late August, straight after flowering, taking the flower stems and a little of the leafy growth — never cut back into the old, bare wood, because it rarely reshoots. Give rosemary a light tidy in spring, removing no more than a few centimetres. Thyme benefits from a shear after flowering to keep it bushy rather than woody. Mint can be cut hard at any point; it will come back with vigour.

Harvesting and carrying the border through winter

Pick herbs in the morning, once the dew has dried but before the sun gets fierce, when the oils are at their most concentrated. Use scissors rather than pulling at stems, and take from the top of the plant so it branches below the cut.

As autumn arrives, lift pots onto feet to keep them clear of standing water, and move lavender and rosemary against a sheltered wall if you can. Cut back on watering but do not let the compost dry out completely. A thick mulch of grit around the crown of each plant keeps winter wet away from the stems. Top-dress with fresh compost in March, and the whole group will come back into scent by early summer — ready to be brushed past, and picked from, all over again.