Ilex aquifolium L.

An evergreen tree up to 80 ft high, of very leafy, much-branched habit, forming naturally a dense pyramidal mass; branchlets often clothed more or less with minute dark down. Leaves glossy dark green, 1 to 3 in. long, 3⁄4 to 21⁄2 in. wide, very variable in size, outline, and toothing. Ordinary seed-raised young trees have very wavy leaves with large, triangular, outstanding teeth 1⁄2 in. long; but as they increase in height the leaves of the upper branches become less spiny, until finally the tops of good-sized trees will be found almost wholly furnished with quite entire leaves. Flowers small, dull white, short-stalked, fragrant; produced during May and June, clustered in the leaf-axils. Berries round, red, 1⁄4 in. diameter, containing two to four nutlets. The common holly may be either male, female, or bisexual.

Native of Europe (including Britain, where it is found wild in all parts except the north-east of Scotland) and W. Asia. The common holly is on the whole the most useful of evergreen trees and shrubs. For providing shelter nothing else equals it, because of its habit of keeping dense near the ground; and during the dark months a holly tree well laden with its bright red fruit is one of the handsomest and most cheerful objects our winter landscape provides. It makes the best of all evergreen hedges.

The holly does not transplant well, and unless it be removed with a considerable amount of soil attached to its roots, this operation can only be done safely either about the end of September or in May, when root-activity has commenced. If the roots have been injured in transplanting, it is a good plan to reduce proportionately the top growth by as much as one-half (see chapter on Transplanting in Vol. I). The common holly should be raised from seed. Being slow of germination it is advisable, as with Crataegus, to mix the berries with sand or fine earth in a heap, which should be exposed for a year to all weathers and turned occasionally. This rots the outer covering and allows the two to four nuts or seeds each fruit contains to separate. They arc then sown (soil and seed together) shallowly. The varieties do not come true from seed, and have to be propagated by cuttings or by grafting. Cuttings are best made of thin side twigs about 4 in. long, with a heel attached, and placed in mild heat. They will also take root under a handlight out-of-doors, but are slower. Grafting is done in spring on the seedlings of the type.

Cultivated, as it has been, for hundreds of years in Britain, the common holly has sported into an enormous number of varieties, most of them hand­some, some curious, and a few worthless. An unfortunate practice, started long ago when they were few in number, has obtained of giving them cumbersome Latin names when colloquial ones would have served quite as well. In the 18th century many variegated hollies were grown under such pleasant names as Eale’s Holly, The British Holly, Glory of the East Holly, Fine Phyllis Holly, Painted Lady Holly. These and many other sorts were described shortly by Miller in the early editions of his Dictionary. Most were still in the trade later in the 18th century but the old names were discarded when Latin epithets became the fashion.

The most authoritative work on holly cultivars is: ‘The Common Holly and its Varieties’ by Thomas Moore, published in fourteen parts in Gardeners’ Chronicle, 1874–6. Dallimore’s treatment in Holly, Yew and Box (1908) is, with acknowledgement, largely based on Moore’s work. The following selection is mainly confined to varieties in commerce or represented in the Kew collection, but many others, not treated, may still be found in old collections.

It may be remarked that all variegated hollies whose variegation is in the centre of the leaf have a strong tendency to ‘run out’, that is, to revert to the green sorts from which they originally sprang, and it is necessary to cut out the green twigs as they appear. The marginally variegated ones do not show such a tendency.

From the Supplement (Vol. V)

For cultivars with yellow or orange-coloured berries, see the article by Susyn Andrews in The Garden (Journ. R.H.S.), Vol. 110, pp. 518–22 (1985).

cv. ‘Argentea Medio-picta’. – This clone is male.

var. balearica – Susyn Andrews has pointed out in her article in the Kew Bulletin, cited under I. perado below, that variants resembling the Balearic holly occur throughout the Mediterranean region and do not merit separate taxonomic status.

var. chinensis – Although certainly allied to I. aquifolium, this should rank as a distinct species – I centrochinensis S. Y. Hu. So far as is known, it is not at present in cultivation. See further in this supplement under I. corallina.

cv. ‘Ferox Argentea’. – This has attained a height of 22 ft and a slightly wider breadth in Mr E. F. Allen’s garden in Suffolk (The Garden (Journ. R.H.S.), Vol. 103, p. 77 (1978)).

cv. ‘Laurifolia’. – According to Elwes and Henry, this is male, but it is uncertain whether all the trees answering to Loudon’s original description (1838) belong to the same clone. Some specimens belonging here are:

Elvetham Hall, Hants, 50 × 41⁄2 ft (1977); Westonbirt, Glos., 66 × 33⁄4 + 31⁄2 ft (1979); Clumber Park, Notts., 66 × 41⁄4 + 41⁄4 ft (1979).

cv. ‘Lichtenthalii’. – There is an old specimen of this rare cultivar at Wakehurst Place, Sussex.

† I. colchica Poyark. – Of recent introduction, this ally of the common holly is a shrub, commonly forming the undergrowth in silver fir or beech forest, and ranging from the Caucasus westward through northern Anatolia to European Turkey and bordering Bulgaria. It differs from the common holly in a number of characters, notably in its not or only slightly undulated leaves or shorter more deeply grooved petioles and with shorter more forward-pointing spines, the terminal one straight and slender.

† I. spinigera (Loes.) Loes. I. aquifolium var. caspia f. spinigera Loes.; I. hyrcana Poyark. – Another ally of I. aquifolium, often forming dense thickets only 3 to 4 ft high in the ‘Hyrcanian’ forests of northern Iran and bordering Russia (Talysch), south of the Caspian, to which it is endemic. The leaves are strongly undulated as in the common holly but on the average smaller and with fewer, impressed pairs of lateral veins. It was introduced by Mrs Ala and Roy Lancaster in 1972 (Journ. R.H.S., Vol. 99, p. 106 (1974)) and again by Fliegner and Simmons for Kew in 1977.

Both these species are discussed by T. R. Dudley in the Mitteilungen of the German Dendrological Society (Mitt. Deutsch. Dendr. Ges.), No. 72, pp. 97–128 (1981), in English.