Read your balcony before you plant a thing

Coastal balconies are generous with light and stingy with shelter. Before you buy a single seed packet, spend a week noticing which way the wind blows in — around most of the UK that means a prevailing south-westerly, so the exposed corner is usually on the left as you look out to sea. Watch, too, where the sun lands at midday and how long it lingers. A south-facing balcony can sit a couple of degrees warmer than the garden below, while a north-facing one may only catch three or four hours of direct light.

Salt is the other invisible influence. Wind-borne salt scorches leaf edges, turns them brown and brittle, and slows growth long before the plant actually dries out. Anything you can do to break the wind — even a little — pays you back in healthier leaves and heavier cropping.

Choose compact, tough and quick

On a windswept balcony, plant size matters more than variety prestige. You want crops that stay small, root deeply enough to hold on, and finish fast enough to beat the weather. Leafy cut-and-come-again crops are the backbone of a seaside container garden because they shrug off a bit of salt burn and regrow within weeks.

• Salad leaves: loose-leaf lettuce such as Lollo Rossa, rocket, mizuna and mustard greens. Sow little and often.
• Radishes: ready in three to four weeks and perfectly happy in a six-litre pot.
• Dwarf French beans: bushy, self-supporting, and far less likely to be shredded than climbing types.
• Chard and kale: Cavolo Nero and Ruby Chard stand up to wind and keep cropping into autumn.
• Tumbling tomatoes: trailing cherry varieties for hanging baskets and tall pots, with the bonus that fruit stays clean.
• Herbs: rosemary, thyme, sage and oregano are made for coastal conditions — they almost prefer it.
• Spring onions, beetroot and chillies: all tolerant of root restriction if watered steadily.

Leave behind anything tall, top-heavy or slow: maincrop tomatoes, sweetcorn, courgettes and full-size brassicas will test your patience on an exposed ledge.

Pots that stand their ground

Small pots are the single biggest cause of failure by the sea. A larger volume of compost holds more water, buffers temperature swings and gives roots something to grip when the wind pushes. Aim for at least ten litres for tomatoes and beans, fifteen or more for anything tall, and group small pots together so they shelter one another.

Terracotta looks lovely but dries out fast in a breeze; glazed ceramic, frost-proof plastic and wooden planters hold moisture far better. Heavy pots are an advantage here — they resist tipping — but check what your balcony can safely carry, and use pot feet or a saucer to lift drainage holes clear of the floor. A saucer also catches the water that would otherwise drip onto the neighbours below. Always use fresh, peat-free compost with added slow-release feed and a handful of grit or perlite for drainage.

Building a windbreak that works

Solid barriers are a mistake: they create damaging gusts on the sheltered side. What you want is a porous screen that filters the wind rather than blocking it. Netting, woven willow, bamboo screening or a few rows of tough plants will cut wind speed noticeably for a metre or two behind them.

• Fix screening to the balcony rail with cable ties, leaving the top third open so air still moves through.
• Place your tallest, hardiest plants on the exposed side and tender crops in the lee.
• Harden off new plants gradually — a week in a sheltered corner before they face the front row.
• Stake and tie tall stems low down, using soft twine in a figure-of-eight so nothing rubs.
• In gales, lay pots on their sides or move them against the wall until the weather passes.

Fleece and fine mesh also work as temporary protection on cold, salt-laden nights in spring.

Watering and feeding without fail

Wind strips moisture from compost far faster than still air, so containers on a balcony dry out roughly twice as quickly as those in a sheltered garden. Check every morning in summer by pushing a finger in to the second knuckle — watering little and often suits leafy crops, while fruiting plants prefer a thorough soak when the surface just begins to dry.

Feed weekly once flowering starts, switching to a potassium-rich tomato feed for tomatoes, peppers and aubergines. A seaweed-based tonic every fortnight is a gentle, salt-friendly boost and seems to help plants recover from wind scorch. A thin mulch of gravel or compost on the surface slows evaporation, and grouped pots with a shared water reservoir or self-watering insert can buy you a weekend away.

Small adjustments that make a big difference

Sow in succession every fortnight from March to August so a bad spell of weather never wipes out your whole harvest. After a salty blow, rinse foliage with a can of fresh water in the early evening. Keep an eye on aphids and whitefly, which shelter in the calm pockets behind your screening, and deal with them by hand or with a soap spray before they build. Finally, remember that coastal light is intense — a shade net over lettuce in high summer keeps it sweet and slow to bolt, while autumn sowings of chard and winter salad will crop on well into November under a cloche.