How to jazz up a gloomy, north-facing wall is one of gardening's greatest challenges.

Hardly any sun reaches the plants and the soil is either dry and gritty or cold and waterlogged. Only a handful of climbers will survive this dense shade and bring life and colour to a dull wall.

When plants grow in more normal, sunny spots, they have an inbuilt mechanism that prevents them from putting their energy into producing overly long stems. Instead, they focus on growing leaves for photosynthesis. As light levels reduce, however, this mechanism is gradually shut off, so plants put their resources into producing longer stems and proceed to rush upward to reach the light. Plants also detect neighbours within 20cm, so try to grow faster and out-perform their rivals. Such plants are known as shade avoiders.

Leggy shade avoiders have few leaves, especially lower down, which means they're not a good choice for gardeners. Fortunately, other plants are not triggered into becoming etiolated. They produce plenty of foliage and are described as shade tolerant. Despite its name, Hedera helix (common ivy) is absolutely fascinating. If you have a specimen, look at the leaves. Depending on location and available light, the size and shape of the leaves can change dramatically. At ground level, ivies grow larger but thinner leaves to absorb light more efficiently. As they reach the top of a wall or a tree and are exposed to more light, they grow smaller leaves. In time, flowering stems bearing a third shape of leaf start to grow.

Ivy is one of the few shade tolerant climbers and, as a bonus, is an evergreen. Many years ago, I had a garden flat in Edinburgh with a six-metre wall at the back. Common ivy had been planted by a previous owner and it blanketed the entire wall. It was a pleasure to see and a welcome haven for birds and insects.

Hedera helix solves many problems for us, sometimes too well. The bridge at the bottom of our current garden is also the base for ivy. It has spread relentlessly along the fence and threatens to throttle some of my favourite climbing roses. I have to rip out great armfuls of the invading vine every autumn to keep on top of it, if only just.

Common ivy thrives in virtually any soil – wet, dry, thin, clay. Ironically, it's so well adapted to its environment that many gardeners would sooner select a less successful plant. Several varieties of Hedera helix are a little less hardy and may suffer from wind scorch but, critically, they grow less vigorously, so are more controllable and better suited to gardens.

Many varieties and cultivars of Hedera helix have been developed, producing a wide selection of variegated leaves. So, if you want to use ivy as green wallpaper, choose one of these ones. Although common ivy grows to at least 10 metres and, uncontrolled, could even weigh down and damage a tree, most of the varieties available for gardeners are much smaller and better behaved.

Buttercup is a beauty. Tolerating almost any kind of soil, it grows slowly to a modest two metres and its subtle pale green – almost lime – foliage is superb. The leaves lighten to yellow in sunnier spots, but that won't happen in a gloomy corner. Another cracker is Glacier. Reaching around three metres, it has grey-green leaves, with silvery, cream veining and edging. Goldchild has yellow margins.

If you have a higher wall to cover, you might prefer a tougher ivy, Hedera colchica. The species form is hardy and grows to around 10 metres, but variegated forms are smaller and a little less hardy. The large leathery-ovate leaves of Dentata variegata are dark green, set off by broad, creamy-white margins. With a good summer and more light than a sunless wall provides, you'd have striking black berries in winter. Sulphur Heart offers gold-splashed leaves and is a bit more vigorous than Dentata. Although we grow all of these hederas as foliage plants, they will flower and produce attractive winter berries when they reach more light at the top of a wall.

As well as having poisonous leaves and sap which irritates the skin, ivy has another drawback. It uses aerial rootlets to cling on to its climbing frame. Although it won't be a problem growing against a wooden or sound brick wall, these rootlets penetrate old mortar, so may cause structural damage. A better option here is Virginia creeper, Parthenocissus. This deciduous climber uses disc-like suckers at the tips of tendrils to cling on, so is not a problem.

All 10 species of Parthenocissus are vigorous climbers, perhaps too rampant for smaller gardens. Two of the hardiest species are P quinquefolia (Virginia creeper) and P tricuspidata (Boston ivy). The dull green leaves of Virginia creeper turn brilliant red in autumn while Boston ivy's show is equally impressive, with superb bright red and purple foliage. Magnificent. n

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