Overlooked, ignored, consciously shunned… ivy has a bad rap. Unfairly so, says Sue Fisher – and here’s why
Hedera or ivy is such a familiar plant that it seemingly needs no introduction. Yet this ultra-tough and versatile evergreen is often unjustly overlooked or even actively avoided due to wariness of vigorous self-clinging stems. But embrace these as virtues, not negatives. Welcome its easy, adaptable and shade-tolerant growth that can go up, down or across, and how it is eminently trainable, with attractive and enormously varied foliage. Plus, ivy is outstanding for wildlife, makes an excellent houseplant or winter pot gap-filler, is great to harvest for festive decorations and has the potential to cool and insulate our homes. Time to put ivy back in the spotlight.
Hedera helix is known as common or English ivy and is the most widely grown and varied species. It offers a wealth of shapes and variegations: more than 100 named cultivars are listed in The RHS Plant Finder.
English ivy is small-leaved while those of other commonly grown species H. algeriensis, Persian ivy (H. colchica) and Irish ivy (H. hibernica) are much larger. Heights range from under a metre to several metres – even tens of metres when mature – so matching variety size to site is vital.
Given the versatility of ivy, its potential sites are many. It could be on supports to create screening or as a faux hedge, as ground cover, in containers, smartly clipped on panels, as standards and on wire shapes to make speedy (and cheap) topiary. Of course, ivy is also an excellent wall climber. Research undertaken by the University of Reading and supported by the RHS into using climbing plants to mitigate extremes of temperature found ivy was the top performer, with an overall average air temperature reduction of 5.7C. Walls stay cooler with shading; surrounding air is cooled by water evaporation and in winter, evergreen foliage also keeps homes warmer.
MUST HAVE plants
While much detrimental press has been given to its effects on structures and trees, ivy is fine on sound walls and has been found to protect surfaces from weathering. Avoid planting where brickwork or mortar is crumbling and keep growth trimmed clear of windows, gutters, or roofs as slender shoots work their way into small gaps and then expand, while the aerial shoots can leave marks. Copper or zinc sheets or anti-graffiti paint can be an effective aid to management on hard-to-trim areas. Healthy trees support ivy with no ill effects: remove only as a precaution from weak trees or those s
