Why your balcony matters more than you might think

Bees, hoverflies, butterflies and moths travel along corridors of food, and in towns and cities those corridors often break at the third floor. A window box of lavender or a balcony crowded with catmint can act as a stepping stone between a park and a back garden, giving pollinators somewhere to refuel exactly when they need it. The encouraging news is that you do not need much room. Even a metre-wide balcony can become a genuinely useful pit stop if you choose the right plants and arrange them thoughtfully. Think of yourself less as a gardener with limited space and more as the person running a very small, very popular café.

Choose nectar-rich flowers, and skip the duds

Many of the showiest bedding plants have been bred for petals rather than pollen, so they offer almost nothing to a hungry bee. Double flowers are the worst offenders: all those extra layers of petal make the nectar physically impossible to reach. Busy Lizzies and most pelargoniums fall into the same category — lovely to look at, but a dead end for wildlife. Instead, look for single, open, daisy-like or tubular flowers, ideally with a strong scent, because scent is a reliable sign that nectar is on offer.

Try to cover the whole season rather than one glorious fortnight in July:

• Early spring: crocus, grape hyacinth, pulmonaria, wallflowers and hellebores.
• Late spring to early summer: catmint, chives, alliums, thyme, hardy geraniums and sweet alyssum.
• High summer: lavender, salvia, verbena, agastache, hyssop, borage, single cosmos, calendula, nasturtium and sea holly.
• Late summer and autumn: sedum, asters, single dahlias, echinacea, rudbeckia and helenium.

Herbs earn their keep twice over. Rosemary, thyme, oregano, mint (keep it in its own pot, always) and chives all feed pollinators, then feed you. Let a few bolt and flower rather than pinching everything back — the bees will thank you for it.

Group your pots for impact and for insects

A single lonely pot is surprisingly hard for a bee to spot. Insects navigate by mass of colour, so three of the same plant placed together will draw far more visitors than three different plants scattered about. If space is tight, plant one generous pot with a single species rather than a mixed basket; a solid block of catmint reads as a signal, whereas a jumble reads as background noise.

Height helps too. Use a tall, sturdy plant such as lavender or a compact buddleia at the back, mid-height salvias and verbenas in the middle, and trailing nasturtium or alyssum to soften the front edge. Larger pots hold moisture better, so aim for 30cm or more across wherever you can. Use peat-free compost mixed with a couple of handfuls of grit for drainage, and stand pots on saucers in summer — on a hot balcony, compost dries out alarmingly fast. Check the weight of what you are planning before you fill anything, particularly on a Juliet or hanging balcony, and move pots rather than heaving them once they are planted up.

Provide shelter, water and somewhere to nest

Food is only part of the picture. Pollinators need somewhere to rest out of the wind, a drink, and ideally a place to raise the next generation.

• Water: a shallow dish with pebbles or marbles gives insects a safe landing pad. Refresh it every couple of days so it does not stagnate.
• Shelter: a dense evergreen shrub, a few grasses left standing over winter, or a small cluster of pots pushed together all create handy microclimates.
• Nesting: a bee hotel with hollow stems, mounted 1–2 metres up and facing south or south-east, suits solitary bees. A small bundle of hollow canes tied together does the same job.
• Litter: leave seedheads and a little leaf litter in a corner over winter. Hollow stems and dry material are prime real estate for overwintering insects.

Skip pesticides entirely. Even the so-called organic ones are rarely selective, and on a balcony there is nowhere for the casualties to come from.

Match your planting to your aspect and the wind

Most nectar-rich flowers want at least six hours of sun, so if your balcony faces south or west you can be generous with lavender, thyme, rosemary and sedum. North and east-facing balconies can still work beautifully with shade-tolerant options: foxgloves, hardy geraniums, fuchsias, Japanese anemones and wood anemones will all flower happily in light shade. Wind is the real enemy up high, so avoid tall, floppy plants in exposed spots and choose sturdier, more compact varieties instead.

If your balcony is a wind tunnel, a simple trellis with climbing jasmine, honeysuckle or a loose willow screen will slow the airflow without blocking light. Group pots closely and stand the heaviest at the edges. Terracotta and glazed pots hold their ground far better than lightweight plastic, which tends to take off in a gust.

Small habits that keep the garden buzzing

Water in the early morning or evening so less is lost to evaporation, and check pots daily through July and August. Deadhead some flowers to keep them coming, but leave others to set seed for birds and overwintering insects. Aim for a little untidiness: a pot of ivy left to flower in autumn is one of the best late-season nectar sources you can offer, and it costs you nothing at all.

Start small if you like — one pot of catmint and a dish of water is a legitimate pollinator garden. Add another pot next spring, then another. Within a couple of seasons you will have something that looks generous, smells wonderful on a warm evening, and quietly does a great deal of good.