I saw a beautiful halesia in a private garden. How do I grow this unusual tree?

D Woodman, Bodmin

The snowdrop tree, Halesia carolina, is a small deciduous tree or large shrub that has clusters of pendulous, bell-shaped white flowers in late spring, then pale-green leaves and winged autumn fruits. To thrive, it needs a sheltered, sunny or semi-shaded spot and a moist but welldrained, lime-free soil. It is quite slow-growing and will eventually reach a height of 12ft-15ft, with a slightly larger spread. Halesia carolina is available from the Tree Shop (01499 600263, www.scottishtrees.co.uk ).

I want to create a drought-tolerant border in a sunny corner. The soil is reasonably light and well drained. Which perennials should I use?

E Rice, Newmarket

Many herbaceous perennials can tolerate long spells without moisture, especially during the summer months. To ensure the plants establish, however, it is important to water the root balls thoroughly before (and just after) planting, then spread a thick mulch over the soil surface. During the growing season, keep the area free from weeds. The best perennials to use are yarrow (Achillea filipendulina), lady’s mantle (Alchemilla mollis), Crambe cordifolia, sea holly (eryngiums), euphorbias, red-hot pokers (kniphofias), Nepeta ‘Six Hills Giant’, Ice plant (Sedum spectabile), Stachys byzantina and verbascums. Certain trees, shrubs and herbs can also be grown in this situation, including arbutus, caryopteris, cistus, cytisus, lavender, rosemary, tamarix and thyme.

Neil Wormald is a qualified horticulturalist.

Send your questions to Garden Expert, Home, The Sunday Times, 1 Pennington Street, London E98 1ST, or e-mail garden.expert@sunday-times.co.uk

Explore Gardens

• Hampton Court Palace Flower Show

• Chelsea Flower Show

Times recommends

• Second homes: credit crunch casualty or money-spinner?
• How I built my own sliding house
• Top 10 incentives for house buyers