Flowering occurs in May and June (2). Holly berries are a very important source of food for birds during winter (4), and birds assist in the dispersal of holly berries away from the parent tree (3). Holly may also spread by vegetative reproduction, by 'runners'; furthermore, the tips of branches that touch the ground may take root, forming a bower around the trunk of the tree, which may be used by animals (and children) as a shelter (3).
Unsurprisingly there is a rich wealth of folklore and custom surrounding the holly tree (3); the amount of berries produced is used as a means of divining whether there will be a harsh winter. A widespread and firmly held belief around Britain is that it is extremely bad luck to cut down a whole holly tree, although somewhat paradoxically, it is permitted to cut branches to bring into the house during winter (3). This belief has often led to hollies being retained even when the entire hedge to which they once belonged was destroyed. In many farming areas, holly has been given to livestock as winter browse, and this practice continues today. Holly wood was used to make horsewhips for many years, as it was thought to have 'power over horses'. It was also believed to provide protection against fire (3). The most well-known holly-custom, however, is bringing boughs into the house in winter. Originally, holly was a fertility symbol because of the retention of the berries and shiny foliage throughout winter. It was also thought to protect a house from witchcraft and goblins. The pagan tradition of bringing holly indoors was accepted by Christianity; the spines of the leaves symbolising the crown of thorns, and the red berries representing the blood of Christ (3).