Country & Garden: A plant is for life, not just for Christmas

TO JUDGE by the number of potted blooms in garden centres and supermarkets at this time of year, plants are as much a part of the seasonal tradition as the Christmas tree. Sales of pot plants are increasing, although not at the same rate as sales of cut flowers, and growers are very aware that they are competing for the same market.

At Christmas, more than at any other time of year, we are looking for something that is immediately attractive: no one wants to buy a plant that will look fabulous in three or four weeks' time. For this reason, according to Kevin Hill, the poinsettia has become the main target for plant shoppers; he is qualified to know, because this year he has grown 200,000 of them at his nursery in Chichester.

Now almost as closely associated with Christmas as mistletoe and holly, this Mexican native was first used in nativity festivals in the 17th century. It is a member of the euphorbia family, but took its name from Joel Poinsett, who first introduced the plant into the United States, from where it found its way to Europe.

Its popularity is a fairly recent development; poinsettias are extremely susceptible to draughts, and it is essential that at every point in the supply chain they should be protected. It is only about 15 years ago that providing supermarkets and garden centres with healthy plants was a very hit and miss affair, because delivery vehicles were unheated. Now, the main threat to a poinsettia is the journey from the till to the house; if it is not protected from the cold, even the trip across a car park could prove fatal.

Assuming that it reaches its destination safely, the poinsettia is ideal for the dry conditions of our centrally-heated homes, as long as its compost is kept damp. Other traditional Christmas house plants like cyclamen and azaleas are less happy in such a warm atmosphere, and need extra attention to compensate. Cyclamen need plenty of water, although they do not like to be waterlogged, and will not flourish if the corms become wet. The secret is to place the pot in a saucer of water, and to keep that topped up, so that the compost remains moist.

Lee Carter, who is in charge of the house plant centre at the Polhill Garden Centre in Sevenoaks, points out the importance of choosing a decent specimen in the first place - and this doesn't necessarily mean the cheapest plant in the display. Cyclamen either look healthy or unhealthy, with little in between.

A plant that is flourishing will have dark green leaves and upright blooms; when it is thirsty, it will suddenly collapse, and the leaves will begin to turn yellow. Poinsettias are more difficult to assess, particularly if they are cooped up in a cellophane sleeve: the bracts should be firm and thick, or they will break as soon as they receive a knock.

Azaleas are also popular at this time of year. They are even more demanding than cyclamen when it comes to watering, and once they have dried out there is little that can be done to save them. While cyclamen like to be moist, azaleas need to be wet; this is best achieved by immersing the whole pot in water and leaving it to absorb as much as possible. The plants also benefit from a humid atmosphere, so they should be sprayed regularly with a mister as long as the flowers last.

There are plenty of other flowering plants that we could choose for Christmas, but as with other seasonal traditions, we tend to stick to what is familiar. And from the growers' point of view, there is so much emphasis on poinsettias that it is difficult to get the shelf space for anything else. Kevin Hill suggests that several varieties of chrysanthemum are worth looking out for: some of the single red blooms, such as Elliot, or Vulcan Time, would look very good in a festive display.

The most challenging part of growing Christmas house plants is what to do with them when they have stopped flowering. The temptation is to get rid of them and start again the following year, but with a bit of effort they can all be coaxed back to life.

Azaleas and cyclamen can be put out into the garden once the danger of frost is over and left until September, when they will start showing fresh signs of life. Poinsettias, however, are more problematic, since they need more than 13 hours of darkness during September and October, in order that that their bracts will turn red. So when this year's red bracts start to wither, buy some black plastic bin liners, cover the plant and wait for the display to reappear in time for next Christmas.