Why a rowan earns its place in a small garden

The rowan, or mountain ash, is one of the most generous trees you can plant in a tight space. It is genuinely native across Britain, from the lowlands right up to the treeline in the Highlands, so it shrugs off our winters, late frosts and wet clay soils without fuss. In return it gives you creamy-white blossom in May, a heavy crop of scarlet berries from late August, and leaves that turn copper, gold and orange before falling.

Best of all for a compact plot, rowans are naturally slender. Many reach only 5 to 8 metres with a spread of 2 to 4 metres, and their roots are fibrous and shallow rather than thuggish, so they can be planted closer to a patio, path or boundary than most trees of similar height. You get the presence of a proper tree without the shadow of an oak.

Check your soil, light and shelter before you buy

Rowans are adaptable, but they are not indifferent. They grow best on a moist, free-draining soil that is neutral to slightly acid, and they dislike sitting in waterlogged ground over winter. If your plot floods after heavy rain, either plant on a slight mound of improved soil or choose something else.

On thin, chalky soils rowans often struggle and yellow, so be honest about what you have. A simple soil test kit will tell you the pH in minutes. Where the ground is sandy or poor, dig in plenty of well-rotted compost or leafmould before planting and mulch afterwards.

• Light: full sun gives the heaviest berry crop and the best autumn colour, but a rowan will tolerate light, dappled shade.
• Shelter: rowans are wind-hardy, but exposed sites can strip the berries and shred autumn leaves early. A little shelter from the prevailing wind is a real advantage.
• Space: check both the ultimate height and, just as importantly, the spread. A 2-metre spread suits a narrow border; a 4-metre spread does not.

Getting the size right for your garden

This is where most planting regrets begin. The wild species, Sorbus aucuparia, can reach 12 metres or more in good ground, which is far too large for most modern plots. Choose a selected form instead, and check the mature dimensions rather than the size of the sapling in the pot.

• Sorbus 'Autumn Spire': narrowly upright, roughly 5 to 6 metres tall and only 2 metres wide. The best choice for a small garden, a courtyard or a narrow frontage.
• Sorbus aucuparia 'Sheerwater Seedling': a dependable upright form with good berries, but it will reach around 8 metres, so it needs a larger garden or a position away from the house.
• Sorbus vilmorinii: smaller and more delicate at around 4 to 5 metres, with ferny leaves and berries that fade from red to soft pink and white. Lovely, but the pink tinge is subtle.
• Sorbus 'Joseph Rock': superb butter-yellow and orange autumn colour with amber berries, reaching around 7 to 8 metres.
• Sorbus cashmiriana: glossy white berries that last well into winter and hold their colour, on a tree of about 6 metres.

If you have very little room, also consider the smaller Sorbus reducta, a suckering shrubby species under a metre tall that can be grown in a large container or at the front of a border.

Berries, birds and the wildlife dividend

The wildlife value of a rowan is out of all proportion to its size. The flat heads of small white flowers in May are a magnet for bees, hoverflies and other pollinators at a time when nectar can still be scarce. The leaves feed the caterpillars of several moths, including the wonderfully named fruitlet mining tortrix.

Then comes the main event. Rowan berries are eaten by blackbirds, song thrushes, mistle thrushes, redwings and fieldfares, and they are one of the favourite foods of wintering waxwings. If you can leave the berries on the tree rather than netting them, a small garden rowan can become a genuine winter spectacle. Different varieties ripen at different times, so if you have space for two, choose one early and one late to stretch the season.

Buying and planting: what to look for

Bare-root trees, available from late autumn to early spring, establish best and cost least. Container-grown trees can be planted at any time of year provided you water them diligently through the first summer.

• Check whether it is a named cultivar or a seedling. Seed-raised trees vary wildly in berry size, colour and autumn leaf, so buy a named form if the display matters to you.
• Look for a clean trunk and healthy bark. Avoid any tree with sunken, oozing patches, which may indicate canker, or with silvery, curled foliage.
• Inspect the union where the cultivar joins the rootstock. It should be smooth and unbroken, with no bulging or cracking.

Plant into a square hole at least twice the width of the rootball, at the same depth the tree was previously growing, and stake only if the site is exposed. Firm the soil, water thoroughly and mulch with a ring of bark chip kept clear of the trunk.

Looking after a garden rowan

Rowans need very little. Water well for the first two summers, then only during prolonged dry spells. Prune in winter to remove dead, damaged or crossing branches, and nothing more. Heavy pruning encourages flushes of weak, upright shoots and spoils the natural shape, so resist the urge to tidy. Remove any suckers that appear around the base, and keep grass and weeds clear of the trunk for the first few years. Do that, and a well-chosen rowan will reward you for decades with blossom, berries, birds and autumn colour in a space most trees could never fill.