Growing Herbs in Containers on a Sunny Patio

Why Herbs Love a Sunny Patio

Most of the herbs we reach for in the kitchen — basil, rosemary, thyme, oregano, sage and marjoram — come from Mediterranean hillsides where the sun beats down, rain runs straight through gravel, and the air stays dry. A sunny patio mimics those conditions surprisingly well. Stone flags and brick walls soak up heat during the day and release it slowly after dusk, so the air around your pots stays a degree or two warmer than the rest of the garden. That warmth is exactly what these plants want, and it also helps intensify the oils that give herbs their scent and flavour.

Pick the brightest spot you have — ideally somewhere that receives six hours or more of direct sun — and keep the pots within easy reach of the kitchen door. You will pick far more often if you only have to step outside with a pair of scissors.

Choosing Pots and Getting Drainage Right

Drainage matters more than pot size, but not by much. A pot of roughly 25–30cm across suits most herbs, and a decent depth lets roots run down rather than round and round.

• Terracotta dries out quickly but breathes beautifully, which suits rosemary, thyme and sage.
• Glazed or plastic pots hold moisture longer — better for basil, parsley and chives.
• Always check the drainage holes, and enlarge them with a drill if they are mean and narrow.
• Stand pots on feet or bricks so water can escape freely instead of pooling underneath.
• Skip the saucer except under basil on the hottest days, and empty it within an hour.

A handful of broken crocks or gravel in the base is traditional, though modern composts drain well enough that it is not strictly necessary. What really matters is that water never sits around the roots.

Compost and Planting Up

Use a soil-based compost such as John Innes No. 2 for woody herbs, and mix in a good handful of horticultural grit per pot to open it up. Basil and parsley are happier in a peat-free multipurpose compost with a little grit added. Add slow-release fertiliser sparingly — too rich a compost produces soft, floppy growth with weak flavour.

Group your sun lovers together. Rosemary, thyme, oregano and sage all enjoy the same lean, free-draining regime, so they can share a large pot or stand side by side. Basil, which drinks more and hates a chill, does better in its own container where you can water and shelter it independently. Keep mint in a pot of its own too — not because it needs different conditions, but because it will otherwise gallop through everything else.

Watering Through Warm Spells

In a heatwave, a terracotta pot can dry out in a single afternoon. Rather than dribbling a little water over everything each morning, water thoroughly until it runs from the base, then leave the compost to dry before watering again. This encourages deep roots and is far kinder to rosemary and thyme, which sulk and yellow if kept constantly wet.

Water early in the morning or in the evening so less is lost to evaporation. A layer of grit or gravel on the surface of the compost reduces moisture loss and keeps the base of the stems dry. If you are away, group pots together in the shade of a wall and stand them in a shallow tray of water — but never leave them standing in it for more than a day.

Watch basil for dramatic wilting on hot afternoons. It usually recovers by evening; if it does not, water it and move it a little further from the wall.

Feeding, Pinching and Fresh Pickings

Herbs grown for leaves need less feeding than flowering plants. A weak liquid feed every fortnight through summer is plenty, and rosemary and thyme barely need that at all.

• Pinch out basil tips regularly to keep plants bushy and delay flowering.
• Snip thyme and oregano lightly and often, never taking more than a third at once.
• Harvest rosemary from the top few centimetres of soft growth.
• Remove flower buds from basil and mint to keep the leaves tender.

Pick in the morning, after the dew has dried, when the oils are at their strongest.

Pests, Weather and Overwintering

Greenfly gather on soft basil tips — a squirt of water usually shifts them. Vine weevil grubs can hollow out rosemary and thyme roots; if a plant collapses for no reason, tip it out and check. Mint occasionally picks up rust, which shows as orange spots on the undersides of leaves; cut the plant back hard and bin the foliage rather than composting it.

Come autumn, move rosemary, thyme and sage against a warm south-facing wall and raise pots onto feet so winter wet drains away. Basil is a tender annual — enjoy it through summer and sow fresh next spring. With a little attention to drainage and water, a modest patio can supply fresh pickings from April right through to the first frost.