Gardening in the city doesn't get any trickier than this. On two tiny, awkwardly shaped balconies — one a skinny corridor, the other a kerchief-sized triangle — Isabelle Palmer grows sweet peas and clematis, two kinds of lavender, hostas, hellebores and hebes, violas and strawberries, any amount of herbs, fragrant lilies and even, for heaven's sake, notoriously tricky delphiniums.
Most ground-level town gardeners can't grow those. The entrance to one balcony is heralded by a miniature version of a front-garden parterre — a bay pyramid surrounded by a ruff of box, in a black-stained planter — and the corner of the triangular balcony is marked with a tree of twisted willow, strung with lanterns. Finches frequently visit the birdhouses on the wall.
Palmer's garden-in-the-sky, above north London's bustling Finchley Road, gives her colour, scent, birdsong, edibles and, most importantly, a refuge from stressful city living.
"Having your own little bit of green in the city to nurture is the best way to relax. High-rise gardening is great: as well as your own turf, you look out on to the skyline and city rooftops," she says.
When she moved several years ago to her maisonette on the third and fourth floor of the Octagon, a remarkable redbrick Victorian building of Gothic arched windows and Moorish cupolas that was once a church, then a synagogue, now flats and offices, 31-year-old Palmer knew very little about gardening.
'It is my refuge. On Sunday mornings I can sit reading the papers, surrounded by colour and fragrance'
"I was working in the City, as a PR with accounts in luxury goods and interiors, and I was time-poor. I knew the look I wanted, but had no idea how to achieve it.
"I needed gorgeous ready-planted window boxes, clever ideas to make the most of the awkward corners, stylish merchandise — anything that would make the balconies feel they were an extension of my living space. I found that garden centres don't cater for balcony gardeners and there were no companies that made container gardens."
Palmer recognised a gap in the market and the idea of a website dedicated to city dwellers with small, tricky outside spaces germinated over a couple of years. She took time out to research, taking short garden design courses at both the English Gardening School and KLC, as well as visiting open gardens both private and public. "Even in the largest gardens, there are always ideas to take away, that you can downsize," she says.
"Gardening on a balcony, grouping plants together, is much like creating a border. And you need a backbone of evergreens, just like in a garden. I was particularly inspired by the Kensington Roof Garden where they grow mature trees in about 13 inches of soil. Do it right, and anything is possible."
Like most gardeners, she learnt through trial and error on her own patch: "I discovered the importance of symmetry. Putting a tall plant in one place and a short plant opposite doesn't work visually. Just like indoor spaces, you need to get the flow right. And trying to grow hostas in full sunshine — not observing the basic mantra of right plant, right place — will fail every time. You can't fight nature, you need to work with it."
Two years ago Palmer finally launched The Balcony Gardener, a one-stop shop for townies who garden on balconies, terraces and rooftops as well as patios and courtyards.
There are potted flowery meadows-to-go for townies who want a touch of the country within sniffing distance, and there are chic zinc troughs planted with architectural evergreens for townies who want their outdoor space to ooze urban cool. There is even a low-allergen window box with pollen-lite plants such as passionflower.
Palmer uses a nursery in Worcestershire to supply plants and a warehouse in the same area that sends out the must-have merchandise: wall-mounted herb racks and tiered plant stands, tight-fit table and chairs, her own range of window box flower and veg seeds (Anthropologie and Liberty's stock them), old wooden fruit crates and faux concrete planters, containers for awkward corners and specially angled brackets to fix them on to railings and sloping walls.
There are cloches and fleeces because, argues Palmer, balcony gardeners need to protect their charges over winter, too. Her version of a tool shed is a compact tool box in a pretty shade of turquoise: everything has to look good, because everything is on show.
"Our market is mostly professionals who say having a kick-start — bringing in a few ready-planted containers that work for their space — has given them confidence. Once they realise they're not going to kill everything, they might buy some seeds, or plant their own windowbox." Palmer's two balconies are the prototype for how high-rise outdoor living can benefit and enrich city life.
"The triangular balcony is my refuge, where I can sit on a Sunday morning and read the papers, surrounded by colour and fragrance. The galley balcony serves as a flowery backdrop for when friends come round; it's just a few inches away from my living room dining table. I couldn't live without my treasured bit of outdoor space. And where balcony gardeners have the edge over ground-level gardeners is that when we move, we can take it all with us."
* The Balcony Gardener: balconygardener.com (020 7431 5553)
FROM THE BALCONY GARDENER'S BIBLE
* Choose interesting containers that area feature in themselves: they will make a small space look bigger. Old wooden crates make great rustic containers.
* Spend money on a few key pieces rather than lots of small pots. Too many bits makes a small space look overcrowded.
* Keep to a colour palette of three shades maximum to avoid a dolly mixture effect. Pinks, purples and whites look especially good together.
* If privacy is an issue, give priority to screening plants such as bamboo or bay.
* Place containers in your sightline, not all on the floor where you look down on them, but opposite a seat, or outside the kitchen window. Make the displays work from the street, too. Use French windows or doors, open or closed, to frame your design.
* Mix a moisture-control gel into compost before planting. It delivers water as and when plants need it. Be prepared to water daily in hot weather.
* Plants in pots soon use all the nutrients in compost; either use a slow-release fertiliser when planting or use a dilute plant food once weekly.
* High-rise gardening means working with the wind, so stake tall plants before they keel over.
* Cover compost with purple slate pieces or Cotswold chippings to retain moisture and give containers a good finish.
* You will still get ground-level pests and diseases on high: keep slug pellets to hand.
Photographs: Clive Nichols