Why a sunny patio suits herbs so well

Few things give more pleasure for such a small outlay than a row of herb pots lined up along a warm wall. A south- or west-facing patio soaks up heat through the day and releases it slowly into the evening, creating the sheltered, free-draining conditions that Mediterranean herbs evolved to enjoy. Rosemary, thyme, oregano and sage all hail from rocky hillsides where their roots never sit in cold, wet soil, and a container on a sun-baked patio mimics that environment far better than a rich border at the bottom of the garden.

There is a practical bonus, too. Herbs grown in pots sit at waist height, so you can step outside mid-recipe with a pair of scissors, snip what you need and be back at the hob in under a minute. Basil picked seconds before it hits the tomatoes tastes nothing like the tired supermarket bunches that have spent a week in a chilled cabinet.

Choosing containers that do the plants a favour

Drainage is the single most important consideration, and it is where most disappointing herb pots go wrong. A container with one small hole in the base, sitting flat on paving, will hold a soggy sump of compost after every watering.

• Size matters. Rosemary needs a pot at least 30cm across and deep; thyme and basil will manage in 20–25cm if you are diligent with watering, but bigger pots are always more forgiving.
• Terracotta looks lovely and breathes well, though it dries out quickly in full sun. Glazed pots hold moisture longer and suit basil particularly well.
• Always raise pots on feet or tiles so water can escape freely and air can circulate underneath.
• Check the holes. If a pot has a single tiny drainage hole, drill one or two more before planting. Crocks or a layer of gravel in the base are old advice but a good-quality, open compost does more good.

The three reliable performers

If you are starting with just three pots, these are the ones to choose.

• Basil. Thirsty, tender and greedy, but unbeatable for flavour. Sweet Genovese is the classic; bush types such as Greek basil are neater and slower to bolt. Give it the warmest, most sheltered spot and never let it dry out completely.
• Rosemary. Woody, drought-tolerant and evergreen, so it earns its keep all year. It resents being fussed over. Plant it in gritty compost, water sparingly once established, and it will shrug off everything except waterlogged roots and hard frost.
• Thyme. Perfect for the front of a pot arrangement, where its tiny leaves and low, sprawling habit soften the edges of taller plants. Common thyme, lemon thyme and creeping varieties all thrive in the same dry regime as rosemary.

Parsley, chives, mint and coriander are worth adding, but keep mint in its own pot — it will overwhelm anything sharing its compost. Coriander and parsley prefer a little shade in high summer and will bolt if scorched.

Compost, planting and spacing

Use a soil-based compost such as John Innes No. 2 for the woody herbs, mixed with roughly a quarter horticultural grit by volume. Basil is happier in a peat-free multipurpose compost with a handful of grit for drainage. Fill the pot leaving a 2–3cm rim below the edge; this lets you water thoroughly without the compost washing over the side.

Plant only one herb per pot unless you are deliberately creating a mixed display, and even then group plants with similar water needs. Thyme, rosemary, oregano and sage can share a large container quite happily. Basil should never be paired with rosemary — one wants damp roots, the other wants dry.

Watering and feeding through the season

In July and August, a 25cm pot in full sun may need watering twice a day. Water in the evening or early morning, aiming at the compost rather than the leaves, and soak until water runs from the base. A finger pushed 2cm into the compost tells you more than a glance at the surface.

Feed basil every fortnight with a general-purpose liquid feed, then switch to a tomato feed once you start cutting heavily. Rosemary, thyme and sage need very little — a light feed in spring is plenty. Rich feeding makes these woody herbs soft, leafy and short on the aromatic oils that give them their punch.

Harvesting, pinching out and winter care

Regular picking keeps herbs compact and productive. Pinch out the growing tips of basil every week or so, always cutting just above a pair of leaves, and remove any flower buds the moment they appear — once basil flowers, the leaves turn bitter and the plant starts to wind down. Sow a second batch in midsummer so you have young plants to replace the tired ones.

Cut thyme and rosemary lightly after flowering, never into old, leafless wood, which rarely regrows. In autumn, move rosemary into a sheltered spot against a wall or under the eaves, and raise pots onto blocks so they never stand in winter wet. Thyme and sage will usually come through a mild UK winter outdoors; basil will not, so enjoy it as a seasonal crop and start again from seed on a bright windowsill in spring.