Ivy is the holly's constant partner, in carols that is.

It has fallen out of favour since its Victorian heyday when ivy garlanded every staircase and twined its way over every festive hearth as a token of luck and prosperity for the coming year.

The fact is that although the experts tell us that ivy's aerial roots won't damage sound walls nor kill healthy trees, we don't quite trust it not to loosen the mortar or strangle our trees. I do my best to stop it climbing the walls because I fear for the soft lime mortar and the eves that can be crept under and through but it has climbed the chimney breast when I wasn’t looking. An ancient lilac completely clothed in ivy was brought down last year to make way for an arch between the garden and the orchard but I did not mourn the passing of either the lilac or the ivy for together they were a dark and gloomy presence.

Yet I do love ivy because it is one of the quiet heroes of our countryside. In its juvenile form it climbs ever upwards with aerial roots that attach themselves to bricks and bark but once it runs out of a bricks or trunk it transforms. Those three lobed leaves become simple ovals and the ivy develops woody side branches such as those pictured. This ivy began life many years ago climbing up the ‘ty bach’, the outside toilet half-way down the garden. When we came here in 1984 the ty bach had all but disappeared and only a couple of decayed posts and the ivy remained. Losing its support the ivy had to stand on its own roots and by necessity developed a thick trunk. It now sports an enormous domed canopy that is supported with a pergola.

I dearly love this ivy for it provides shade when I wish to sit under it in summer and at this time of year I pick bunches of its berry and leaf rich twigs. A month or two ago the ivy began to flower attracting so many bees and other pollinating insects that the buzz could be heard before I entered the garden and now those flowers have turned into berries. They will ripen and become black just at the time when the birds need them for they pack a powerful protein punch.

You can take advantage of ivy’s transformative nature by taking a cutting from ivy in its mature stage and it will grow into a neat shrub that will flower in due course and never revert to its climbing form. But ivy on a trellis or fence is marvellous. What could possibly be better, on a dark winter day, than the ivy 'Buttercup' splashing its soft yellow leaves over a dull boundary? It is undoubtedly one of the prettiest and most decorative of all the ivies but it does need sunshine to maintain its bright colour, planted in dense shade it will sulk and turn pale green. There are a host of pretty, variegated forms but 'Goldheart' with primrose yellow centres and the silver variegated 'Glacier' with a neat, white edging to its leaves are two of the best. Happy Christmas.