The neglected leaf of England (or why holly isn't just for Christmas)

A table adornment; a wreath on a door; a sprig on top of a pudding. Is there any plant with a more time-limited, one-dimensional appeal than holly?

A table adornment; a wreath on a door; a sprig on top of a pudding. Is there any plant with a more time-limited, one-dimensional appeal than holly?

But anyone who has ever wondered if Ilex aquifolium was more than a mere Christmas decoration should take a trip to the Royal Botanic Gardens in Kew, south-west London, and head for the Holly Walk. It's not internationally famous, like the Palm House. There are not even any signs directing visitors to the walk, in contrast to the Bamboo Garden or the Rhododendron Dell. It's one of Kew's lesser-known attractions, almost an afterthought or secret.

It has to be pointed out to you. The Holly Walk lies along the course of a track, running for more than half a mile through the middle of the gardens, which until the 18th century was the main road between Richmond and Kew Bridge, known as Love Lane.

It separated the country estates of George II, and his son Frederick, Prince of Wales, who died before succeeding him as monarch.

Now, with the two estates long since merged and the main road running elsewhere, it is merely a tarmacked path behind the Evolution House and the Temperate House. But when you realise what it was, you can readily imagine the ancient highway. And it is lined with what is probably the best holly collection in the world.

The collection was begun in 1874 by Sir Joseph Hooker, the eminent 19th-century botanist who was director of the gardens and also Charles Darwin's great friend. (Darwin confided his explosive theory of natural selection to Hooker before anyone else; he told him it was like confessing a murder).

It consists of about 700 bushes and trees of 135 different species and varieties and is one of the few places where the great variety of the holly family can be readily observed. Much of it consists of variations on the theme of I. aquifolium, which is the common English holly, familiar to us all with its glossy dark green leaves and bright red berries. There are dozens of I. aquifolium cultivars, or specially bred varieties, on display.

Many have attractive variegated leaves, such as I. aquifolium Silver Milkmaid where the dark green foliage is boldly splashed with bright yellow; others have elegant shapes, such as Perry's weeping holly, which looks like a spiny version of a weeping willow ( I. aquifolium Argentea Marginata Pendula); yet others take spinyness to new heights, such as hedgehog holly ( I. aquifolium Ferox) which looks infinitely worse than barbed wire. Ray Townsend, the man who looks after the Holly Walk, said: "You just touch it and it's lethal."

Mr Townsend is the manager of Kew's arboretum, the 15,000-strong tree and shrub collection in the gardens. He is a bamboo specialist (one of the world's leading experts) but also loves holly species and has collected them in Japan.

"This is probably the best collection in the world," he said. "It's certainly the oldest."

He was full of holly information: all species are evergreen; most have spines. For holly berries to be produced, a male plant needs to be growing near to a female plant; berries on some species can be pale yellow, bright orange and almost black, as well as the familiar bright scarlet; and a plentiful crop of berries usually does not last long as they are quickly eaten by birds.

He said that as well as I. aquifolium there were hollies from all over the world, such as Ilex opaca, the American holly, which is much paler and a substantial tree, or Ilex pernyi from southern China, whose small multi-spined leaves signal another bush with wicked prickles.

But to many people common holly is perhaps the most attractive variety. It has roots deep in our culture, and its presence in our houses at Christmas seems to stem both from Christian tradition and from earlier pagan lore, both Germanic and Celtic.

The holly wreath is often thought of as representing Christ's crown of thorns at the crucifixion, with the red berries representing the drops of Christ's blood.

But the plant seems to be a magical one - like another red-berried tree, the rowan - in Celtic lore and in Germanic lore too. Its evergreen leaves symbolised continuing life in the dead of winter, and it was believed to keep away witches from your house.

All the more reason to display a few branches. And if it catches your interest, Kew's Holly Walk is for you.