Evergreen, ever-popular hollies

There are many good reasons to plant hollies in your garden.

They are long-lived evergreen shrubs with year round appeal. They are excellent wildlife plants; the tiny flowers are a source of food for insects and the winter berries valuable food for wild birds. The cut foliage is traditional for festive decoration, so a supply of fresh material close to home is welcome. What is more a holly planted near the front door will ward off evil spirits; a holly left to grow in your hedgerow will deter witches that may be using the hedge top as a travel route.

Hollies have been revered and cultivated since ancient times. Although there are both deciduous and evergreen species it is the larger evergreens that are most familiar. Surprisingly the British native Ilex aquifolium and its cultivars are not hardy enough for colder climates. In the US and colder parts of Europe the cultivars ofIlex x meserveae are grown instead. With smaller, much darker leaves than common holly Ilex x meserveae is tougher and hardier.

With its increasing pest and disease problems gardeners are becoming wary of planting common box, Buxus sempervirens. I lex crenata is small and compact and makes a valuable substitute. There are several cultivars with different growth habits and leaf forms. The upright Ilex crenata ‘Caroline Upright’ is particularly valuable in small and narrow planting spaces.It works well in containers in courtyards and on balconies and needs little maintenance.

Ilex aquifolium and Ilex x altaclarensis cultivars are the ones that are grown as large shrubs or small trees. Both tend to be sparse and open when young, filling out as they mature.Regular light pruning helps to promote a bushy habit and good soil conditioning is essential for healthy growth. They are evergreen shrubs to plant for the long term.

Small container grown plants establish easily but that a few years to make an impact.It is worthwhile planting larger plants where possible and certainly container grown specimens are more certain to establish. If planting field grown plants careful handling of root-balled plants is essential; damage to the roots prior to planting can result in failure.

There are many named cultivars with both plain and variegated leaves. The names are confusing: those with masculine cultivar names are usually females that bear fruit and vice versa. Some female varieties require a male pollinator, others such as Ilex aquifolium ‘J.C. van Tol’ are self-fertile. Never assume that Ilex aquifolium will produce berries, unless the plants are female. However the ratio of female to male plants in seed-raised stock can be as low as 1:18.

The variegated hollies are some of the most handsome evergreens for gardens. Those with green and white variegated leaves are perhaps the most versatile and easiest to incorporate. Ilex aquifolium ‘Argenteo Marginata’, the broad-leaved silver holly, has deep green leaves with creamy-white edges and pink-tinged young shoots.It is a female holly that produces abundant red berries in the presence of a male pollinator.

Ilex aquifolium ‘Elegantissima’ makes a good planting partner. It is similar in leaf but is male, so without fruits. An excellent structure shrub the variegation is subtle but will still liven up a backdrop of plain evergreens.

Ilex x altaclarensis ‘Golden King’ is the best known of the golden variegated hollies. It is easy to grow and has broad leaves which are almost spineless with bold, gold margins. A female variety it fruits prolifically and seems to retain its berries for longer when other plainer hollies are quickly stripped by the birds. A mature specimen develops a broad conical shape and makes a fine specimen.

With the demand for effective screening trees in restricted spaces pleached trees have become popular. There are few successful types: photinia grows quickly and soon makes an impact, but needs regular pruning.Quercus ilexis slow to start and a rather dark and uninteresting backdrop.Prunus laurocerasusis bold and instant but soon gets out of hand and is high maintenance.The self-fertileIlex ‘Nellie Stevens’ gives excellent results with its dense growth and dark green, shining, spineless leaves.It fruits prolifically in early winter and only needs annual pruning.

Some holies retain a more bushy habit. Ilex aquifolium ‘Ferox Argentea’ is the silver variegated form of the oldest holly in cultivation. The curiously rolled leaves have spines on the surface, as well as around the edges. Random and bushy in habit it is a good choice for underplanting deciduous trees and is very shade tolerant.

Ilex aquifolium ‘Myrtifolia Aurea Maculata’ is another bushy variety. Slow to grow it has small leaves boldly splashed with gold and very glossy. A perfect plant to brighten a shady corner in a small garden.