Start with an honest survey of your balcony

Before you buy a single seed packet, spend a fortnight actually watching your balcony. Which way does it face? A south- or west-facing spot with six or more hours of summer sun will carry tomatoes, chillies, cucumbers and climbing beans. East-facing is gentler but still generous, ideal for salads, herbs, chard and radishes. North-facing is the hard case, but not hopeless: leafy crops and mint will crop steadily if you shelter them and keep your expectations modest.

Wind matters just as much as light. An upper-floor balcony behaves like a wind tunnel, and the gusts will find the corners and the open ends first. Note where plants get battered, because that is where you will need a screen or a toughened, low-growing crop.

Then weigh things up, literally. Check your lease or ask your landlord about loading limits before you fill the space with heavy pots. A saturated 30cm container of compost can weigh 25–30kg, and a row of them adds up quickly. Keep the heaviest pots close to the wall or over a supporting beam, and spread the load rather than clustering everything in one corner.

Pots, compost and the weight question

Size beats quantity every time. One 30–40cm pot will out-crop three thin, undersized ones, because a decent root run holds moisture and buffers temperature swings. Terracotta looks lovely but dries out fast in wind; glazed ceramic, frost-proof plastic or fabric grow bags are more forgiving. Whatever you choose, check for drainage holes and stand pots on feet so water can escape freely.

Use a good peat-free multi-purpose compost for annual crops, and mix in a handful of soil-based compost for anything you plan to keep over winter, such as rosemary, bay or strawberries. Add slow-release feed at planting, and top-dress with gravel, wool pellets or cocoa shells to slow evaporation and stop compost splashing onto your neighbours below.

• Self-watering containers are worth the money on exposed balconies; a reservoir buys you a day.
• Square pots fit together with less wasted space than round ones.
• Saucers help in a heatwave but must be emptied after rain, or roots will rot.
• Pot feet or bricks lift containers clear of the surface and improve airflow.

Crops that earn their place in a small space

Choose varieties bred for containers rather than trying to tame a full-size vegetable. Bush and trailing tomatoes such as 'Tumbling Tom' or 'Garden Pearl' need no staking and crop happily in a 30cm pot. Chillies and compact aubergines thrive in the extra warmth a sheltered balcony offers. 'Hestia' runner beans and 'Tom Thumb' peas give you pods from a single container, while 'The Sutton' broad beans suit a deep pot.

For roots, look for short, round types: 'Paris Market' carrots, 'Pablo' beetroot and 'Cherry Belle' radishes. Leaf crops are the most reliable of all — chard, spinach, rocket, land cress and cut-and-come-again lettuce will keep producing for months from a modest trough. Tuck herbs in wherever there is a gap, but give mint its own pot, or it will take over everything else.

Growing upwards when floor space runs out

Vertical growing is how a small balcony suddenly feels twice the size. A wall-mounted trellis, a railing trough, or a simple frame of bamboo canes will carry climbing beans, peas, cucumbers and trailing tomatoes without stealing a centimetre of floor.

• Railing planters for herbs, salad leaves and strawberries.
• Stacked or tiered planters for lettuce, radishes and spring onions.
• Trellis or netting fixed to the wall for beans, peas and cucumbers.
• Hanging baskets for tumbling tomatoes and trailing nasturtiums, which also bring in pollinators.

Remember that anything above waist height dries out faster and catches more wind, so plant the most drought-tolerant crops up there and check them daily.

Watering, feeding and coping with wind

Wind is the great thief of balcony growing. It strips moisture from leaves faster than sun alone, which is why exposed pots can dry out twice as quickly as you would expect. Water in the morning, aiming at the compost rather than the foliage, and water thoroughly until it runs out of the drainage holes — little-and-often sips only dampen the surface and encourage weak roots. In hot, breezy spells, check twice a day.

Don't assume rain will do the work. Wind-driven rain mostly misses upright pots, and anything under an overhang stays dry through the wettest week. Group pots together to create a microclimate, mulch the surface, and consider a simple drip or capillary watering system if you are out at work all day.

Start feeding once flowers appear. Tomatoes, peppers, courgettes and beans want a high-potash tomato feed weekly; leafy crops prefer a gentler, nitrogen-rich feed every fortnight. A mesh windbreak — never a solid screen, which simply creates damaging turbulence — will protect tender growth without blocking light.

A rhythm for the growing season

Sow little and often rather than everything at once. A short row of salad seed every two or three weeks from March to August gives you a continuous supply instead of a single overwhelming glut. Harden off anything raised indoors, and hold back tender crops until the risk of late frost has passed in your area.

Balconies sit high, so pollinators can be scarce. Tap tomato plants gently each morning or tickle the flowers with a soft brush to set fruit. Watch for aphids, whitefly and red spider mite in hot, still corners, and plant French marigolds, calendula and nasturtiums to bring in hoverflies and lacewings. Clean pots, fresh compost and good airflow prevent most problems before they start.

Above all, treat your first season as an experiment. Note what cropped well, what sulked in the wind, and where the sun actually falls. A productive balcony is less about gadgets and more about learning the particular habits of your own small, windswept patch of Britain.