How to care for Sarcococca, the evergreen Christmas box plant

At first glance, sweet box (Sarcococca) may not seem to be a showstopper plant, but easily earns its place in any size of garden, being bombproof, shade loving, evergreen, and compact. However, come winter, it suddenly steals the show with scent. On still days, from December to March, its flowers flood the air with a high-pitched honey perfume that is so strong, it can spread many metres. These potent blooms are not visible from a distance, being very small; they are bristly, white (and sometimes pink), and coat the stems over a long period.

There are 15 species of Sarcococca, which are mostly found in the forests of China, as well as other parts of Asia. The plant's Latin name comes from the Greek sarkos (fleshy) and kokkos (seed), refering to the berries the plant produces. These are purple, red, or black and follow the flowers, often enduring for months.

Sweet boxes are slow growing to between 60 centimetres and 2 metres and usually spread, making them excellent groundcover plants. Because their leaves are glossy, they inject shady parts of the garden with light. Armed with other winter shade lovers, such as hellebores, mahonia, and Cyclamen coum, the shady corner can become the best bit of the garden during the cold months.

Sarcococca is also a great wildlife shrub. Along with mahonia, hellebores, and heather, it is one of the few nectar sources for winter-foraging bees – particularly honeybees. On the rare occasion that honeybees are out of their hives in midwinter –either because they're very hungry or because it's sunny – or if they're foraging in early spring, they will hunt out sweet box, making it a great plant for beekeepers.

As if all that wasn't enough, Sarcococca is excellent for hedging, if you want to grow a low evergreen divide in semi-shade or shade. Being part of the box family, it responds well to clipping and its glossiness makes it an elegant, smart hedge.

This wonderful little shrub is not widely grown, but should be, since it offers so much to the garden (it will even grow in dry shade) and performs whether given minimal TLC or ignored entirely.

The most widely grown sweet box is good old Sarcococca confusa, which reaches 1 to 2 metres, has shiny dark-green ovate leaves, strongly scented ivory blooms, and black berries. S. ruscifolia var. chinensis 'Dragon Gate' is another fabulous form, slightly faster growing and smaller than S. confusa, with red berries. S. hookeriana var. digyna 'Purple Stem' is also relatively compact and has gorgeous maroon stems in spring; its winter flowers are pink white, and it has attractively dense, bushy growth.

All three are hardy. If you live in one of the mildest parts of the country, there is a bigger range of sweet box to try growing. Crûg Farm nursery, who do their own plant hunting, sell a great range of sarcococca, including tender types and hardy forms, such as compact S. hookeriana 'Crûg's Purple Tips', which has claret-tipped flowers, and spreading red-stemmed S. taiwaniana.

For pots, choose one of the smaller sweet boxes. Both S. hookeriana var. humilis  and S. hookeriana Winter Gem are dwarf froms and exude a wonderful scent.

Choose a spot in semi-shade or shade; rich moisture-retentive soil is best, but sarcococca will tolerate dry shade. If necessary, fork in organic matter (such as compost or leafmould) before planting. These compact shrubs also do well in pots.

• Soil: A rich, fertile, retentive soil is ideal.
• Moisture: Sweet boxes enjoy moisture, but they will grow in dry shade and on chalk, if you force them to. If planting in a parched place (such as in sun or under a tree), fork in organic matter (compost, for instance) to boost retention, and water regularly (especially in hot, dry weather) until established.
• Light: Sarcococca fares well in shade or part shade. It can be grown in sun, but must be watered regularly in warm, dry summers, otherwise it will sulk.
• Hardiness: The widely available species of sweet box are hardy in most parts of the UK, yet it's wise to shield them from very cold wind.
• Nutrients: Mulch (for example, with compost) in spring or autumn or both; you could also give the plant an annual dose of general fertiliser in spring.
• Pruning: An annual prune is not necessary, but they can be cut back after flowering, in spring, if need be.
• Hedging: Being part of the box family, sarcococca can be clipped into low hedges, like regular box (Buxus sempervirens), with the advantage that they don't suffer from box blight and thrive in shade. Of course, they don't have the tiny leaves of regular box, meaning their lines will never be as sharp, and thus they're not as good for topiary or knot gardens. But as a low evergreen hedge that is stress free, sarcococca is a great choice. The best times to trim it are after flowering, in early spring (its main annual haircut), and after it puts on new growth, in June (a lighter shaping clip). Two of the best forms for hedging are Sarcococca ruscifolia var. chinensis 'Dragon Gate' and S. hookeriana var. humilis.
• Pests and diseases: Sweet box can be susceptible to honey fungus; other than that, it's trouble free. Slugs and snails slide past it.

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