Branch out with a tree for all seasons

There is nothing better in the garden to mark the seasons than a tree — and no better time to plant one than now, during National Tree Week (November 24 - December 2), which officially launches the start of the winter tree-planting season.

If you have a shady corner that needs transforming, plant a trio of silver birches to make striking white silhouettes that look ethereal even in winter gloom. Add a scattering of lilac crocuses and some springtime hellebores at their base, and you have a sylvan glade that looks positively magical in springtime. Alternatively, you could invest in just one spectacular multi-stemmed silver birch. Himalayan birch Betula utilis Moonbeam has wonderfully luminous white bark and dark green, glossy leaves, and is suitably compact for small gardens.

Crab apples stay on the tree for most of winter, making the finest festive baubles

Ask any garden designer which small tree tops their list of great all-rounders, and the answer will inevitably be Amelanchier lamarckii. This is the happy-in-shade, elegantly spreading tree that, in spring, is smothered in starry white blossom accompanied by small, slim, copper-coloured leaves. The effect is breathtaking. Then, for an encore, it produces deep red fruits in summer, when the leaves are vibrant green before turning crimson and gold hues in autumn. If you just have room for one tree, this is the one to choose.

A crab apple is a good choice for any kind of small garden. It's a great mixer, suiting an informal border, a spot on the lawn or even a half-barrel on the patio or rooftop. None, in my opinion, is better than Malus Red Sentinel, which has a mass of pink-budded white flowers in spring but peaks in autumn, with fruit-like glossy red cherries hanging among the colourful foliage. Best of all, the crab apples stay on the tree for most of winter, making the finest festive baubles.

If you're going to plant an evergreen tree, make it a beauty: Arbutus unedo, the strawberry tree that has a shrubby habit and fittingly carries an RHS Award of Garden Merit. The glossy, rich green leaves are an attraction, and so is the rough, reddish bark — but in autumn it produces clusters of bellshaped cream flowers just as last year's ripening yellow fruits are turning cherry-red. If you can only offer the strawberry tree a patio or courtyard, it's perfection in a pot, but keep it in a sunny, sheltered spot.

You could summon up the Mediterranean with a silver-leaved olive tree, bare-trunked so you can plant lavender or sow scarlet poppies at its base. Many Londoners are discovering that although an olive tree does well in a pot, it positively thrives when planted in the ground, and is remarkably resistant to frost. Easy to prune — just cut back stems that become too lengthy — the graceful olive tree has replaced the silvery weeping pear in our affections; after all, in a good summer you'll have olives, too. Plant the tree in a sunny position, in free-draining soil, and cut out rogue branches that may spring from the base.

The Judas tree is a rarity in London, yet it is one of the most beautiful trees of all, and needs absolutely no pampering.

See Cercis siliquastrum at its finest in the Generalife Gardens at the Alhambra, Granada, or in Beth Chatto's gravel garden in Essex, where every spring the small, deciduous tree is covered in gorgeous hot-pink flowers that sprout, exceptionally, from the bark itself, including the trunk. The leaves appear just after the first flowers and are pale green, large and prettily heart-shaped. If you're more a fan of foliage than flowers, you might prefer Cercis canadensis Forest Pansy, which has same shaped leaves that are a glorious reddish purple, but fewer flowers. It's a tough call.