Plant now for the fragant flowers of viburnums, writes VAL BOURNE

Most early-flowering viburnums have fragrant flowers in soft pinks or whites and these pastel flowers make the perfect overhead canopy for plummy hellebores or the dark maroon tulip Queen of Night'. It's still possible to plant one now on most soils, as long as the weather isn't freezing. However, if you have heavy, cold clay, any planting should wait until April or even May.

If you are planting purely for scent, the best fragrance belongs to Viburnum x bodnantense Dawn'. This large upright shrub, found at Lord Aberconway's Bodnant garden, has the spiciest hyacinth scent of them all. It's more suitable for the back of a border or a boundary hedge because it can reach at least 10ft in height, but the fragrance carries for yards.

Dawn' will begin to produce pink flowers in autumn, while still in leaf, and go on in bursts, finally finishing with a flourish in late March and the rich, hyacinth fragrance of Dawn' is always at its best in the dreariest of gardening months, November.

For that reason alone, Dawn' is worth a place in every garden and the dark, almost-chocolate stems make a perfect foil for the pink flowers. Viburnum x bodnantense Deben' is paler, the pink buds unfold to produce white flowers. However, Dawn' always seems superior in my eyes.

One of the parents of V. x bodnantense is a hardy shrub first collected in China by Reginald Farrer (1880-1920) and subsequently named V. farreri (syn V. fragrans). The sweetly fragrant, white form called Candidissimum' produces clean-white flowers on bare upright stems. The new leaves are bright green and they frame the pure flowers beautifully. It's an exquisite winter flowering shrub.

But there are other spring-flowering forms also worth seeking out for their fragrant flowers. Viburnum carlesii, known as the Korean Spice Viburnum, is a rounded, medium-sized deciduous shrub. It produces round, grey-green leaves in April and these frame the clusters of pink buds which open to produce lily-scented, blush-white flowers.

The flower heads are delicate and airy and forms of D. carlesii also have good, reddish autumn colour and they can produce black fruits. There is a fine named form, Diana', which bears pink flowers. Another, Aurora', has red buds that open to pink flowers, and forms of V. carlesii tolerate drier soils.

V. carlesii is a parent of a hybrid called V. x carlcephalum and the Latin translates as large-headed carlesii', indicating that this viburnum has large, globular heads. The flowers are primrose-scented and I always found the heads too oversized to enjoy. You may like it though. It is a parent of Eskimo', a small viburnum that produces white snowballs of flower in late spring.

I think the easiest of the spring viburnums to grow is an evergreen called V. x burkwoodii. This has V. x carlesii blood too and it produces small, pink pompoms of flower set on the ends of the stem. Anne Russell' is compact and Park Farm Hybrid' is a later, larger-flowered version. The deciduous V. x juddii forms a small rounded bush and the fragrant delicate heads of pink-white flowers appear in late spring.