Start by Reading Your Balcony's Conditions

Before you buy a single pot, spend a week simply noticing how your balcony behaves. Which way does it face? How many hours of direct sun does it actually get in June, and again in November? Where does rain pool, and where does wind funnel between the walls? A sheltered, south-facing balcony in Bristol will bake, while a north-facing one in Edinburgh stays cool and damp. Neither is a problem — but they call for different plants and different furniture.

Measure properly, too. Note the width, the depth and the height of the railing or parapet. Most narrow balconies are only around 90cm to 1.2m deep, which means anything deeper than 40cm starts to eat your standing room. Write the numbers down and keep them in your pocket when you shop. Almost every mistake made on a small balcony comes from buying something beautiful that simply does not fit.

Go Up, Not Out: Vertical Planters and Wall Greenery

On a narrow balcony, the floor is precious. Your vertical surfaces — walls, railings, the back of the door — are where the greenery lives. The aim is to leave a clear strip of floor for your feet and your chair, and let the planting rise around you.

• Fabric pocket planters hung on a wall hold a surprising amount of herbs and salad leaves, and they dry out faster than pots, so line them with a cheap capillary matting.
• Rail-hung troughs clip onto a balcony railing and give you a metre of colour without touching the floor. Use lightweight peat-free compost and check the fixings can take the weight when wet.
• Trellis or taut tension wire fixed between two walls supports jasmine, clematis or ivy. Star jasmine is fragrant in summer; ivy is evergreen and forgiving in shade.
• A tiered or ladder-style shelving unit lets you stack small pots vertically and rotate them as the light changes.

Wet compost is heavy. A 30cm terracotta pot filled and watered can weigh over 15kg, so never hang anything from a railing that could swing or fall onto the street below. If you rent, check your agreement before drilling into walls.

Choose Plants That Forgive a Forgetful Watering Can

Balcony pots dry out fast. Wind strips moisture even on dull days, and a hot afternoon can finish off a thirsty plant by teatime. The answer is drought-tolerant herbs and a few tough ornamentals that shrug off neglect.

• Rosemary, thyme, sage, oregano and winter savory all prefer poor, gritty soil and full sun. They will sulk if you cosset them.
• Lavender in a generous pot looks wonderful and smells better; trim it after flowering but never into old wood.
• Mint must have its own pot, or it will conquer everything else within a season.
• Sedum, sempervivum and small ornamental grasses give texture and structure if you want more than herbs.

Use a peat-free multipurpose compost with a handful of horticultural grit mixed through for drainage, and top-dress the surface with gravel. That gravel does two jobs: it slows evaporation and keeps the compost from splashing onto your windows during rain. Group pots close together so their foliage shades the soil, and water in the morning or evening rather than at midday.

Folding Furniture That Earns Its Space

Your balcony is a room, and a room needs somewhere to sit. The trick is to choose pieces that vanish when you are not using them. A small folding bistro table and two matching chairs will seat two people comfortably, then fold flat against the wall in seconds. A wall-mounted drop-leaf table is even better on very narrow balconies — it takes up no floor space at all until you lift it.

Round tables work better than rectangular ones in tight corners, and aluminium or acacia frames survive the British weather far better than painted steel. Add a folding stool that doubles as a side table, and a slim storage bench that swallows cushions, secateurs and a watering can. Take soft furnishings indoors overnight; a waterproof storage box that also serves as a seat is worth its footprint.

Turn It Into a Room: Light, Scent and Softness

What separates a balcony from a green retreat is atmosphere. Hang festoon lights on a timer so they come on before you get home, and place two or three lanterns at different heights for depth. An outdoor mirror on the wall opposite the view bounces light back into the space and makes it feel twice as wide.

Softness matters. A polypropylene outdoor rug in a muted colour warms the floor and hides tired tiles. Screen your neighbours with a reed or bamboo roll, or grow a climber up tension wires. For scent, plant night-scented stock and lavender near where you sit, and let jasmine scramble overhead. The result is somewhere you want to linger with a cup of tea, even in a drizzle.

Looking After It Through the British Year

In winter, lift pots onto feet so they drain freely, and move the most tender plants against a sheltered wall. Terracotta can crack in a hard frost, so consider glazed or plastic pots for anything permanently outside. Water far less, but do not stop entirely — evergreens still lose moisture on mild, windy days.

Come spring, scrape off the top few centimetres of compost and replace it with fresh, then feed with a slow-release granules. In summer, water in the cool of the day and deadhead regularly to keep flowers coming. In autumn, clear fallen leaves from any balcony drain before the rain arrives, or you will find a small pond outside your door. Do these few things and your narrow balcony will reward you every single season.