Most hollies are easily cultivated in sun or half-shade in an average garden soil, alkaline to acidic, avoiding extremes of wet or dry.
Most evergreen hollies flower in spring, in the leaf axils of the previous year’s shoots.
The flowers are small, with four petals. Male flowers are produced in crowded clusters with prominent pollen-covered stamens; females have prominent green ovaries.
Male and female flowers are found on separate trees. A non-fruiting holly might be a male plant or a female plant with no pollinating male within bee-range.
Any male holly should be able to pollinate females of the English and Highclere hollies. Sometimes a male holly from a neighbouring garden will do the trick, but if space permits, it is worth planting a male cultivar as a companion nearby.
Reliable pollinators for large spaces include I. x altaclerensis ‘Hodginsii’; in middle-sized spaces try I. aquifolium ‘Laurifolia’ or the gold-margined I. aquifolium ‘Laurifolia Aurea’ (pictured below).
Holly hedges are one of the joys of British gardens. Most of the hardy evergreen hollies available in the UK can be used as a hedge or screen but few can match the English holly for all-round quality and effect. Most cultivars of I. aquifolium, particularly those of a dense, bushy nature, will soon knot together to form a hedge of rich texture. Plant young, at 60cm tall or so, and 60-75cm apart in the row, preferably in autumn. Once established, keep in shape by trimming annually in August with shears or a hedge-trimmer.