There are not many plants that flower in winter, but those which do are most welcome. Winter flowers are commonly not as flamboyant as those of summer, and are usually much smaller – in some cases hidden and almost invisible. But, given much more severe weather conditions at this time of year, it is surprising they manage to flower at all. However, it is not surprising that winter flowers depend on sweet scent to attract pollinating insects, which are scarce in the colder months and only operate best on the warmer, sunny days, the same weather and bright light opening the flowers.

Sweet box or Christmas box, Sarcococca digyna, is a waist-high evergreen shrub. Its flowers have no petals, just pollen-carrying stamens, and they are pale-green to cream in colour. But the flowers carry a sweet, lingering scent, so freely produced as to be caught on the air on a mild, calm winter’s day. It flowers for Christmas in most years, or shortly afterwards, and the stems can be brought indoors where they will last for a few days in water and yield their scent.

Two forms of the fragrant viburnum, Viburnum bodnantense and Viburnum farreri, are quite well known. They carry tufts of pink-white, small, tubular flowers at the ends of small twigs from November through to March, flowering more profusely in a mild spell. The flowering is quite effective and can be seen from a good distance. In summer the plant is rather dumpy and nondescript, but in winter it is a star. The scent is sweet, the typical viburnum scent with a touch of cloves. This plant also cuts well for use indoors.

The flowers carry a sweet, lingering scent, so freely produced

Often starting to flower this month, the witch hazels are renowned for their sweet, light perfume, which is light and unmistakable. The plant forms a large bush or small tree and its spidery flowers carried along bare branches are truly remarkable. The witch hazel is a plant deserving of a position of prominence, ideally with a dark backdrop where sunlight can shine through to highlight the flowers. It should be near a path where its scent can be appreciated. The flowers, though seemingly flimsy, are amazingly resistant to cold.

Daphnes will be flowering soon. The best known of the group are the tall, wonderfully scented Daphne bholua and Daphne mezereum, a purple-flowered kind that carries its flowers on bare branches from February, with the leaves appearing soon after. There is a lovely white-flowered form too. Daphne bholua is variable, but can reach to over 2m in a narrow shape. The flowers are tufted at the tips and sides of branches – small, tubular florets packed together. The colour is a lovely wine-pink, shading out to white.

Mahonia has been in flower since October, but continues through to spring. The bush carries large, spiky, evergreen leaves that are composed of about 20 holly-like leaflets. It makes a large, broad bush with upright tufted stems and the flowers in a crown right on top. The long, narrow racemes of flowers carry small, individual, yellow flowers and the plant is striking in appearance and colour through the late autumn and winter.

The fragrance carries even though it is very light and delicate, and reminiscent of daffodils. The earliest daffodils will soon provide their light scent. Snowdrops, which are related to the daffodil, are often well scented too, especially the larger kinds.

Winter heliotrope is slightly like sweet heliotrope but it is a bad weed. A relative of the honeysuckle, Lonicera purpusii, it’s a shrub of medium size. The flowers are sweetly scented. It might be placed towards the back of a mixed border where it could blend into the background in summer but be noticeable in winter.

Apple canker

A severely damaging disease of apple trees, apple canker shows itself clearly at this time of year. The affected branches carry large cankers – areas of dead skin with dark, stained wood. When the infection has been present for a couple of years, the healthy tissue close to the canker swells into a rounded shape. Canker kills the bark first and if a ring of bark is killed, around a young shoot for instance, the entire shoot or tree dies, leaving a pointed, dry twig. Canker is greatly favoured in high rainfall areas and if dung is used, making the tree soft.

Apple canker.

Whenever canker is seen, it should be cut out, carefully going over the tree to cut out all sources of infection, because the disease is spread by spores from existing cankers. The disease can be spread while carrying out this pruning, or any pruning, and if cankers are pruned the secateurs can be disinfected with bleach after each cut. Normal pruning can then be carried out.

This week

Fruit, vegetables and herbs

Fruit tree pruning can be carried out, except on plums. Fruit trees and bushes can be planted if the soil is not too wet. Overgrown herb plants can be cut back, or divided and re-planted. Compost heaps can be dug out and the compost spread for digging in. Control weeds around vegetables.

Trees, shrubs and roses

Check on young, deciduous trees for bad forking habits and retain only the single strongest lead shoots. Delay tree planting if the ground is very wet, because drainage can be affected in the root zone and this can lead to heavy losses. Roses can be pruned at any time.

Lawns

It can be very damaging to the soil structure of a lawn to run a mower over its surface when it is wet, but there will be occasional spells of dry weather when the ground will firm up enough to mow and this can be done occasionally to keep lawns neat. Trim or re-cut the edges at borders too.

Flowers

Put a few pansies or cyclamen for colour in containers or use some evergreen plants to give life to the garden close to the house entrance. If the ground is wet, do not undertake division and re-planting. Many flowers react very badly to being moved into cold, wet ground.

Greenhouse and house plants

Ensure that house plants are not too close to a source of heat and are not left behind curtains on a cold night. Clear out the greenhouse and wash the glass inside and out, to increase the penetration of light. Water sparingly and do not feed, as it is not necessary.