The Holly and Ivy

A near-mature ivy plant with partially developed fruit and holly in the background (10.12.2009)

This weekend I avoided the Christmas shopping for an hour and took a walk to our local wildlife pond. The surrounding area is suburban with houses and gardens, roads, a golf course, a good network of paths, hedgerows, grassed areas, boggy bits and residual forest. Two plants that are particularly conspicuous in the hedgerows at this time of year are holly and ivy. They have been used as Yuletide decorations for centuries and are linked in the well known carol. Ivy seems to have done particularly well in recent years. It has become something of a nuisance in my garden. Walking along I began to wonder why…

Two closely related species of ivy grow wild in the British Isles. Hedera hibernica is found in the west and in Ireland whereas Hedera helix is common in the rest of the country. They are difficult even for botanists to distinguish and have only recently been identified as separate species. Both are members of the Araliaceae, a plant family that thrives for the most part in warmer climates. The British Isles are at its northern limit.

Ivy is one of the few British plants with distinct juvenil leaves

Ivy has an unusual life cycle for a temperate plant. It flowers late in the autumn, when most other plants are dying back. The berries ripen to a rich black in late winter. In severe cold weather, the flowers and fruit can be badly damaged, making ivy a sensitive barometer of climate change. It has thrived in our region in recent mild winters. Next time someone says climate change isn’t happening, ask them how much ivy they pulled out of their garden last year…

In the early spring, Ivy berries are a valuable food source for hungry birds

David Green

Curator of Mineralogy