Val Bourne on the plants that add colour to Christmas and flowerbeds beyond

I always feel duty-bound to write about euphorbias at least once a year because Oxford Botanic Garden has a Plant Heritage collection containing 152 taxa.

The hardier ones, some 101, are mostly in the family beds although you will find them all over the garden. At the moment there is also a euphorbia trial at RHS Wisley so do try to look at one or other in spring and early summer. Garden-worthy euphorbias combine wonderful foliage with tiny star-shaped flowers that are surrounded by showy bracts that can last for months. Some, such as Euphorbia amygdaloides ‘Purpurea’ , have amazing winter rosettes and early spring flowers.

Others die down in winter, but explode into growth and provide acid-yellow flowers later on. The foot-high mound of E. polychroma, which flatters miniature blue bulbs brilliantly, is one of my favourite spring events at Spring Cottage. Another is the combination of fiery orange found on the shade-loving E. griffithii. I also love E. sikkimensis which flowers in July with my orange-red crocosmias. I am, after all, a fully paid-up member of Plantaholics Anonymous.

However the Botanic Garden also has a collection of 50 euphorbias inside the greenhouses. One of most famous euphorbias of all, particularly at Christmas, is the poinsettia or E. pulcherrima. Its species name actually means the most beautiful euphorbia of all and it could have been designed for Christmas with its bright-red halo and festive green foliage. The red halo consists of long-lasting leafy bracts, rather than soft petals that shrivel up quickly, and this allows the poinsettia to look regal for up to 12 weeks or more. Not surprisingly, these ornamental lovelies have been used as Christmas ornaments for almost a hundred years.

The poinsettia, which was discovered by Joel Poinsett in 1825 in Mexico, has been associated with Christmas for centuries. An old legend recalls that a poor Mexican boy, unable to afford a proper present to take to church, picked some of these colourful red ‘weeds’ as his Christmas gift.

Their ability to grow and spread in warm countries has seen them colonise lots of different areas. In the Canary Isles, for instance, they grow as low hedges all along the roads.

Poinsettias also thrived in the canyons and scrub close to Beverley Hills and Hollywood.

A young rancher, Albert Ecke, admired them and planted them on his own ranch. Ecke began selling poinsettias from Californian roadside stalls in the 1920s.

Their Hollywood glamour soon rubbed off and homes all across America wanted their own poinsettia at Christmas, especially when they saw them in the Christmas movies.

Albert Ecke’s ranch still produces 80 per cent of all poinsettias grown in America. Thirty different poinsettias are grown, but the soldier-red ones are still the most popular. They are raised from cuttings taken from large ‘mother plants’ but they need a lot of heat, a constant temperature of 18C/64F, and even-length days to flower. As a result, some British growers have stopped producing them due to the cost, but there are still British-bred poinsettias on offer in major outlets.