Name: rhododendron

Botanical name: rhododendron, which means the red tree.

Family: heather family. Although the large tree, rhododendrons and the small, alpine kinds do not look alike, they are sent plant family, the Ericaceae, the Erica or heather family.

While the main flowering of rhododendrons takes place in spring and early summer, there are a few invaluable kinds that flower early. These are mostly species from the Far East, imported to Europe in the 19th and early 20th centuries. They have long been prized by lovers of rhododendrons but, strangely, are not well known generally. It might be expected that plants that flower so early would be much sought-after, and this is the case to only a limited degree.

The rhododendron variety that caused the most stir is ‘Christmas Cheer’ which was once forced in greenhouses to flower for Christmas, hence the name. It is sometimes seen in old gardens. Despite the name it does not naturally flower for Christmas except in the mildest areas in an early year. ‘Chrismas Cheer’ is pink, fading out to almost white with frilly flowers; it is a pretty variety.

The earlier-flowering variety ‘Nobleanum Venustum’ is a large-growing old variety of great beauty when in flower in winter – it can start as early as late winter and continue well into spring with its large clusters of rose-red flowers and, like the ‘Christmas Cheer’, it is mostly seen in old gardens and there are pink forms too. These kinds are quite hardy; there is never any damage by frost to the buds or leaves, although open petals can be damaged by hard frost.

‘Nobleanum Venustum’ can make a very large bush more than three metres high and even wider, whereas the ‘Christmas Cheer’ is not as vigorous. But either one is well worth having at this time of year for the touch of colour they bring at a time when the number of flowering plants is limited. These varieties are not easy to find in garden centres, but they are worth watching out for.

Many of the early-flowering kinds are from mountainous parts of China where the climate is cool and damp. The red-flowered tree rhododendron, Rhododendron arboreum, can reach a massive size in its Himalayan homeland but perhaps one-fifth of that here. But then most specimens of these trees are not much over one hundred years old here. This is a magnificent plant for a large garden, and ideal for a country garden where there is space to let it grow.

One of the earliest to flower is Rhododendron dauricum with small trusses of purple-red flowers. In a good year it can cover itself with brilliant flowers in late winter. The pretty, broad-throated lavender-purple or rosy purple flowers are carried in little clusters and open during mild spells in late winter and early spring.

‘Seta’ is a very pretty rosy-red colour as the buds open in February. The first flowers usually open before the end of that month, certainly by early March. The flower tubes are very pale pink, the flared mouth a deeper shade. The bush is small, about one metre, and rounded, covered with flowers. It is quite hardy, unlike other early-flowering kinds, but should be planted on a slope as a precaution, so that cold air can flow down and away from it. Also plant it so that the flowers are out of the first morning sunlight.

Two small-growing kinds that flower early are ‘Shamrock’ and ‘Cilpinense’. Shamrock makes a low bun and covers its surface with sulphur-yellow flowers. Its earliness can vary a lot depending on the season and in a cold season, it can be slow to flower. ‘Cilpinense’ is also slow to flower in a cold spring but can be quite early if the winter is mild. It has very beautiful white flowers, flushed pink.

Neither of these is very frost-hardy and the open flowers and part-open buds can be damaged by a hard frost but usually there are other buds to open later. All of the rhododendrons mentioned need a neutral or acidic soil. Use organic material to reduce the lime content and heavy mulches applied every couple of years. Rhododendron are largely surface-rooting and can be accommodated in this way.

Odd jobs

Tidy-up ornamental grasses

Ornamental grasses tend to get a bit messy from early autumn and some people cut them back at that stage. This can be very damaging and often kills the plants eventually. The grass tops should be left in place until late winter or early spring to get the benefit of their decorative value and to allow the remaining green leaves to continue to photosynthesise during winter and keep the plant going.

Grasses should not be cut back as it weakens them and spoils their natural appearance. About now, the withered grass foliage can be tugged away quite easily in most cases or trimmed off if it does not pull away. Be careful with the saw-edges of some grasses, especially pampas grass, the foliage of which must be cut away. By ‘combing’ out the loose withered leaves the plant is refreshed in appearance and not spoiled.

This week’s reminders

Flowers

Snowdrops and crocuses are beginning to make an appearance. Seeds of geraniums, lobelia, busy lizzie and bedding begonias can be sown in a heated propagator, but it is still too early for most of the easy kinds, such as dahlias and marigolds.

Fruit, vegetables and herbs

Sow seeds of early varieties of cabbage, cauliflower, carrots, lettuce and onions under protection to raise plants for planting out in April. Seed potatoes of early varieties can be put into a greenhouse or bright place to sprout now; this allows earlier harvesting.

Trees, shrubs and roses

The ground has dried out somewhat but it is still very wet for planting in areas of heavy ground. If hedging or sapling trees have been purchased, they can be kept for weeks before planting by being heeled-in to a trench. Roses can be pruned at anytime.

Lawn

There has been quite a lot of wet weather and ground has been very wet on occasion. If an opportunity arises, mow the lawn but otherwise stay off lawns until the recent heavy rain has drained away. Moss control can be carried out using lawn mosskiller.

Greenhouse and house plants

Greenhouse grape vines and peach trees will be starting to come out of dormancy, and they should be encouraged by gaining as much sun heat as possible – the earlier the flowers, the earlier the fruit next summer. Clean the glass to admit more light