<P> The northern and eastern limits are at about the − 2 ° C (28 ° F) winter isotherm, while to the west and southwest, it is replaced by other species of ivy . Hedera helix itself is much more winter - hardy and survives temperatures of − 23.3 ° C (− 9.9 ° F) (USDA Zone 6a) and above . </P> <P> The ivy is widely cultivated as an ornamental plant . Within its native range, the species is greatly valued for attracting wildlife . The flowers are visited by over 70 species of nectar - feeding insects, and the berries eaten by at least 16 species of birds . The foliage provides dense evergreen shelter, and is also browsed by deer . </P> <P> In Europe, it is frequently planted to cover walls and the government recommends growing it on buildings for its ability to cool the interior in summer, while providing insulation in winter, as well as protecting the covered building from soil moisture, temperature fluctuations and direct exposure to heavy weather . Further uses include weed suppression in plantings, beautifying unsightly facades and providing additional green by growing on tree trunks . </P> <P> However, ivy can be problematic . It is a fast - growing, self - clinging climber that is capable of causing damage to brickwork, guttering, etc., and hiding potentially serious structural faults, as well as harbouring unwelcome pests . Careful planning and placement are essential . </P>

When did english ivy come to north america