Why Herbs Belong on a Small Balcony

Herbs are, almost without exception, the most generous plants you can grow in a confined space. They ask for little — a pot, decent compost, a spot with a few hours of sun — and in return they give you handfuls of fresh flavour, a green corner to glance at while the kettle boils, and, if you let a few flower, a small private nature reserve for bees and hoverflies. Even a north-facing ledge barely a metre wide can carry three or four pots. The trick is choosing the right herbs, the right containers and a watering rhythm that suits balcony life rather than a garden border.

Choosing Pots, Compost and a Position

Size matters more than style. Herbs in tiny pots sulk and bolt; herbs in generous pots crop for months. Aim for containers at least 15–20cm across and 20cm deep for the herbs below, with a drainage hole in the base and a saucer or tray beneath to protect your balcony floor and your neighbours below.

• Terracotta looks lovely and lets roots breathe, but dries out quickly in wind. Line the inside with a piece of cardboard or choose a slightly larger size.
• Plastic or glazed ceramic holds moisture far better, which matters on a windy balcony where drying happens twice as fast as in a garden.
• Peat-free multi-purpose compost is fine for basil and mint. For thyme, rosemary or oregano, mix in a good handful of horticultural grit or sharp sand to improve drainage.
• Raise pots onto feet or bricks so water drains freely and slugs have less easy access.

A south or west-facing balcony is ideal; most culinary herbs want at least four to six hours of direct light. If your ledge faces north, concentrate on mint, parsley and chives, which tolerate shade far better than basil or thyme.

Three Herbs That Earn Their Keep

Basil is the one people most often kill, usually by watering it like a houseplant. It wants warmth, sun and steady moisture — damp, not sodden. Sow seed in late spring, or buy a supermarket pot and split it into three or four smaller pots rather than leaving the seedlings crammed together. Pinch out the growing tips regularly to keep it bushy, and never let it flower unless you want the seed. A windowsill in a warm kitchen suits it beautifully; a cold, windy balcony corner does not.

Mint is the easiest herb in Britain and the most thuggish. Always give it its own pot — it spreads by underground runners and will smother anything sharing its compost. A 25cm pot is about right. It enjoys partial shade and slightly damp soil, so it is perfect for that gloomy corner where nothing else thrives. Keep it picked, and cut it back hard mid-season for a fresh flush of tender leaves.

Thyme is made for balconies: tough, drought-tolerant, evergreen in most of the UK, and quietly beautiful when its tiny flowers open in early summer. It hates sitting wet, so use a gritty compost and a terracotta pot, water only when the top centimetre feels dry, and let it bake in full sun. Common thyme, lemon thyme and creeping thyme all work. Snip sprigs with scissors rather than pulling at the stems, which can uproot the whole plant.

Watering, Feeding and Coping with Wind

Balconies are exposed places. Wind strips moisture from leaves and dries compost faster than you would believe, so check pots daily in summer — push a finger in to the first knuckle and water if it feels dry. Water in the morning so foliage dries before evening, which reduces mildew. In hot spells, a saucer of water beneath the pot buys you a day of grace.

• Feed every fortnight from June to August with a diluted liquid seaweed or tomato feed. Container compost runs out of nutrients surprisingly quickly.
• Shelter from strong wind with a lightweight screen, a trellis, or by grouping pots together so they protect one another.
• Turn pots a quarter turn each week so plants grow evenly rather than leaning towards the light.

Harvesting Well and Feeding Wildlife

Regular picking makes for healthier plants. Take basil leaves from the top, never more than a third of the plant at once. Cut mint stems back to a leaf joint. Snip thyme sprigs lightly and often. If you want to overwinter thyme and rosemary, move them against a sheltered wall and ease off the watering — soggy winter compost kills more herbs than frost does. Basil is annual; sow again next spring or take cuttings in late summer.

Here is the loveliest part. Let a few thyme plants, chives or oregano flower rather than cropping every stem. Those small purple and pink blooms are magnets for bees, hoverflies and butterflies, and a cluster of pots on a city balcony can become a genuine stepping stone for pollinators moving through built-up areas. Add a shallow dish of water with pebbles for insects to drink from, avoid sprays entirely, and leave the faded seed heads standing through winter — they feed goldfinches and look rather beautiful frosted on a January morning. A tiny balcony, tended gently, is a wildlife garden too.