My cavalier way with roundheads

EXPERIENTIA DOCET - experience teaches - was the motto of an establishment that I passed through far too quickly to be taught anything at all. So I go on planting bulbs in quantity, even though experience should have taught me that only half of them will live to grace a second spring.

They enjoy light soils more than the heavy, sticky clay that I have, and do not seem to be fooled by the sand and grit I tip around them at planting time. Daffodils, snowdrops, De Caen anemones, scillas, brodiaeas, aconites, hyacinths and crocus thrive reasonably well. But tulips dwindle. So do lilies and alliums, but that has not stopped me ordering quantities of new bulbs, this year in such quantities that we have been living on courgettes and tomatoes on toast for three weeks to cover the cost.

Alliums are top of the bill - in more ways than one. These are ornamental onions with large spherical heads made up of hundreds of individual flowers. The biggest grow on 4ft stems, the smallest will fit into a sink garden. Not all have the characteristic oniony smell.

The first one I ever bought was Allium cernuum which, being a North American native, is used to cool, moist soils. It grows 12-18in high and has flowers that droop round the central head, but this is a positive droop rather than a disconsolate one. The usual colour is a deep rose-pink and the leaves are narrow, yet lush, rarely disappearing altogether. It started life in a group of small black violas called 'Molly Sanderson', but gradually disappeared from that berth, seeding itself into the path instead. It flowers in July and August.

Allium christophii, the next one I tried, needs hotter, drier conditions than A. cernuum. It is also fussier about drainage, but is worth the fuss because it is extremely showy both in flower and after, when the whole head has bleached to a creamy straw colour. It takes a long time to fall apart. The individual flowers have six narrow petals, but you tend not to see them as individuals. The mass is what matters, the whole construction resembling a geodesic dome.

The flower head is about 8in across, balanced on a stout stem about 12-18in high. The leaves are a disaster, dying noisily just as the flower is coming up to its best. Disguise this by planting the allium between, for instance, irises, which enjoy the same conditions and have handsome leaves for the alliums to borrow. You could also grow them behind a low mound of purple sage, which would provide equally good foliage.

This year I am going for the grand slam, the big one, Allium giganteum: footballs balanced on 4ft stems. I picked up the bulbs at the Royal Horticultural Society's Great Autumn Show, where the Independent recently arranged a private view for readers (for a special offer on next week's show, see the coupon below.) The bulbs are monsters. The flower heads are similar to A. christophii but appear later, in July rather than June. The extra height is useful, too. At Hidcote, the National Trust garden in Gloucestershire, these alliums are used down the back of a border of double peonies. They would also make good companions for the supreme foliage plant, Melianthus major, perhaps with agapanthus later.

All alliums are built on roughly the same lines, a stem with a blob on top. The differences have to do with the proportion of one to the other. A. christophii is squat, top-heavy, but has sufficient presence to overcome its inbuilt design problem. A. azureum has 2ft stems which lead you to expect something rather splendid at the top. In fact the flower is only about an inch across, but the colour is a good, clear sky-blue. If you plant enough of them the effect is excellent, particularly when they poke through a low sea of something greyish, perhaps a prostrate form of Artemisia stelleriana.

For the smell as much as anything, I shall plant more jonquils, a variety called 'Quail', this autumn. The leaves are dark and grassy, not at all an eyesore when dying. 'Quail' is about 14in high and appears in April with thickly textured flowers of deep golden-yellow. It will fill in ground between slatey-blue primroses.

'Minnow' is smaller and earlier and needs a hotter position than 'Quail', for it is a tazetta narcissus from the Mediterranean, used to sunbathing in summer. 'Minnow' is only about 7in high and produces up to four flowers on a single stem, the colour soft yellow, the trumpet slightly darker than the surround. Both need well-drained soil. If yours is heavy, dig in some grit before you plant and set the bulbs on sharp sand in the planting hole. Bonemeal helps, too, providing nutrients to help develop roots and flowers.

Bulbs that grow in shade are particularly useful, though there are not enough of them. The Spanish bluebell, Scilla campanulata, is excellent under trees and among the greenery of shade-loving ferns. The flower stem does not droop to one side, like the English bluebell, but stands upright with the flowers ranged all round it, like a rather sparse hyacinth. The white variety is the best, very pure and icy, especially among the newly emerging fronds of shuttlecock ferns or contrasted with the dark leathery foliage of Euphorbia robbiae.

It seeds itself, but not in such a determined manner as our native bluebell, which is a bully in the garden. As well as the white, it comes in dark or mid-blue and a washed-out pink, which is the least successful colour. The blues are excellent in mixed plantings with late narcissi, such as 'Pheasant's Eye'. These are unrivalled for smell, and have elegant papery flowers with tiny snub-nosed centres, deep yellow ringed with red.

'Pheasant's Eye', being a well-proportioned flower, looks good growing in wild situations, but it is late which, if you are planting in grass, can be a disadvantage, though its overall style is exactly right for natural situations. When you are choosing bulbs for naturalising, avoid overbred monsters; they will look as out of place as Madonna at a WI coffee morning.

The Tenby daffodil, Narcissus pseudonarcissus obvallaris, naturalises well, being a wild thing itself. It is early. The leaves are in scale with the flower and not too dominant in their death throes. N. cyclamineus types such as 'February Gold' also look good in grass. This has a long, narrow trumpet and slightly swept-back petals, all the same bright gold colour. I have yet to see it out in February, but presumably that is when it first flowered in the cosy greenhouse in the Netherlands where it was bred, a hybrid between N. cyclamineus and N. pseudonarcissus. 'February Silver' came from the same cross but is a much paler flower, the petals cream, the trumpet a wan yellow.

For more information on alliums, read Alliums by Dilys Davies (Batsford, pounds 17.99). Michael Jefferson-Brown's Narcissus (Batsford, pounds 25) is heavy on breeding but interesting on history and cultivation. Rupert Bowlby's catalogue lists a wide variety of alliums. It is available (send two second-class stamps) from Gatton, Reigate, Surrey RH2 0TA (0737 642221). Avon Bulbs has the narcissi 'Quail' and 'Minnow' at Burnt House Farm, mid-Lambrook, South Petherton, Somerset TA13 5HE (0460 42177). Send four second-class stamps for catalogue.

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