
Ilex aquifolium
Ilex aquifolium
Safety & Hazards
Ilex species in general contain several potentially toxic compounds, particularly saponins, glycosides and triterpenoids. These compounds also often have a range of potential health benefits[1, 2, 3]. The berries are usually the part of the plant most likely to be toxic, though the degree of toxicity is usually low. Their bitter flavour usually prevents a person eating more than one or two, but even a small handful of the fruit eaten by a healthy adult is unlikely to cause more than feelings of nausea that can lead on to vomiting and diarrhoea[2]. The compounds in the leaves are particularly interesting. The leaves of many Ilex species around the world are commonly used to make health-promoting teas that, when drunk on a regular basis, help to regulate bodily functions and can reduce the risk of heart disease, lower blood-cholesterol levels etc (See Ilex paraguariensis or Ilex kaushue for examples)[3]. Even these teas, however, if taken in very concentrated doses, can act as a laxative or cause vomiting. Indeed, several species are used by traditional peoples to induce vomiting as a means of purifying the body (see Ilex guayusa or Ilex vomitoria for examples)
Cultivation Details
Plants require a minimum July temperature of 12°c for good fruit production[4]. They tolerate short periods in winter down to -15°c[5]. Severe frosts can kill whole branches, especially if they are open to the sky[4]. The young growth in spring can be damaged by late frosts. Succeeds in most soils, including peat, chalk, gravels, sand and shales[4], so long as they are not water-logged, though wild plants are occasionally found in situations with standing winter water[4]. Grows well in heavy clay soils[4]. Established plants are fairly drought tolerant[4]. Dislikes dry soils according to one report[6] whilst another says that it succeeds in dry shade[7]. Tolerates a pH range from 3.5 to 7.2[4]. Succeeds in full sun or fairly dense shade[8, 9, 6], self-sown seedlings from woods and shady places making the most shade tolerant plants[9]. Tolerant of maritime exposure[10] though in such a situation it may lose some or all its leaves in the winter[4]. A very ornamental plant, there are many named varieties[11]. Flowers and fruits are formed on wood of the previous year's growth[12]. A good bee plant[13], the minute flowers are sweetly scented[14]. The fruit is a valuable winter food source for birds. Resents root disturbance, especially as the plants get older[15]. It is best to place the plants into their permanent positions as soon as possible, perhaps giving some winter protection for their first year or two[PFAF]. Only move the plants in late spring or, preferably, in early autumn[16]. Plants are quite slow growing, even when in good soils and situations[15, 10]. Trees are usually dioecious but hermaphrodite forms are available. Male and female plants must usually be grown if seed is required. Plants are capable of regenerating from the main stem both above and below ground level and, although the top may be killed in a fire, the plants will usually regrow from the base[4]. Rabbits are particularly fond of this species and will quickly remove the bark. This species is notably resistant to honey fungus[17].
Propagation
Seed - best sown as soon as it is ripe in the autumn in a cold frame. It can take 18 months to germinate. Stored seed generally requires two winters and a summer before it will germinate and should be sown as soon as possible in a cold frame. Scarification, followed by a warm stratification and then a cold stratification may speed up the germination time[18, 19]. The seedlings are rather slow-growing. Pot them up into individual pots when they are large enough to handle and grow them on in light shade in a cold frame for their first year. It is possible to plant them out into a nursery bed in late spring of the following year, but they should not be left here for more than two years since they do not like being transplanted. Alternatively, grow them on in their pots for a second season and then plant them out into their permanent positions in late spring or early summer. Give them a good mulch and some protection for their first winter outdoors. Cuttings of almost ripe wood with a heel, August in a shaded position in a cold frame. Leave for 12 months before potting up. Layering in early autumn. Takes 2 years. Cite as: Temperate Plants Database, Ken Fern. temperate.theferns.info. 2026-02-21. <temperate.theferns.info/plant/Ilex+aquifolium>
Pollinators
Bees
References
- [1]Illustrated Flora of North Central Texas — Diggs, Jnr. G.M.; Lipscomb. B. L. & O'Kennon. R. J · Botanical Research Institute, Texas. · 1999 · http://artemis.austincollege.edu/acad/bio/gdiggs/NCTXpdf.htm · ISBN 1-889878-01-4 ↩︎An excellent flora, which is also available on-line.
- [2]Poisonous Plants of North Carolina — http://www.ces.ncsu.edu/depts/hort/consumer/poison/poison.htm ↩︎An excellent concise but comprehensive guide to toxic plants that grow in N. Carolina. It lists even those plants that are of very low toxicity, including several well-known food plants such as carrots and potatoes.
- [3]Genus Ilex L.: Phytochemistry, Ethnopharmacology, and Pharmacology — Fan Yi, Xiao-ling Zhao, Yong Peng, Pei-gen Xiao · 2016 · http://10.1016/S1674-6384(16)60044-8 ↩︎
- [4]Planting Native Trees and Shrubs. — Beckett. G. and K. · Jarrold · 1979 · ISBN - ↩︎An excellent guide to native British trees and shrubs with lots of details about the plants.
- [5]Shrubs. — Phillips. R. & Rix. M. · Pan Books · 1989 · ISBN 0-330-30258-2 ↩︎Excellent photographs and a terse description of 1,900 species and cultivars.
- [6]Shade Plants for Garden and Woodland. — Brown. ↩︎
- [7]The RHS Gardener's Encyclopedia of Plants and Flowers — Brickell. C. · Dorling Kindersley Publishers Ltd. · 1990 · ISBN 0-86318-386-7 ↩︎Excellent range of photographs, some cultivation details but very little information on plant uses.
- [8]Flora of the British Isles. — Clapham, Tutin and Warburg. · Cambridge University Press · 1962 · ISBN - ↩︎A very comprehensive flora, the standard reference book but it has no pictures.
- [9]Plants for Shade. — Knight. F. P. · Royal Horticultural Society. · 1980 · ISBN 0-900629-78-9 ↩︎A small but informative booklet listing plants that can be grown in shady positions with a few cultivation details.
- [10]Shelter Trees and Hedges. — Rosewarne experimental horticultural station. · Ministry of Agriculture, Fisheries and Food · 1984 · ISBN - ↩︎A small booklet packed with information on trees and shrubs for hedging and shelterbelts in exposed maritime areas.
- [11]Ornamental Shrubs, Climbers and Bamboos. — Thomas. G. S. · Murray · 1992 · ISBN 0-7195-5043-2 ↩︎Contains a wide range of plants with a brief description, mainly of their ornamental value but also usually of cultivation details and varieties.
- [12]The Complete Trees of N. America. Field Guide and Natural History. — Elias. T. · Van Nostrand Reinhold Co. · 1980 · ISBN 0442238622 ↩︎A very good concise guide. Gives habitats, good descriptions, maps showing distribution and a few of the uses. It also includes the many shrubs that occasionally reach tree proportions.
- [13]Garden Plants Valuable to Bees. — International Bee Research Association. · International Bee Research Association. · 1981 · ISBN - ↩︎The title says it all.
- [14]Scented Flora of the World. — Genders. R. · Robert Hale. London. · 1994 · ISBN 0-7090-5440-8 ↩︎An excellent, comprehensive book on scented plants giving a few other plant uses and brief cultivation details. There are no illustrations.
- [15]Trees and Shrubs Hardy in Great Britain. Vol 1 - 4 and Supplement. — Bean. W. · Murray · 1981 · ISBN - ↩︎A classic with a wealth of information on the plants, but poor on pictures.
- [16]RHS Dictionary of Plants plus Supplement. 1956 — F. Chittendon. · Oxford University Press · 1951 · ISBN - ↩︎Comprehensive listing of species and how to grow them. Somewhat outdated, it has been replaced in 1992 by a new dictionary (see [ 200 ]).
- [17]The New RHS Dictionary of Gardening. 1992. — Huxley. A. · MacMillan Press · 1992 · ISBN 0-333-47494-5 ↩︎Excellent and very comprehensive, though it contains a number of silly mistakes. Readable yet also very detailed.
- [18]Propagation of Trees, Shrubs and Conifers. — Sheat. W. G. · MacMillan and Co · 1948 · ISBN - ↩︎A bit dated but a good book on propagation techniques with specific details for a wide range of plants.
- [19]Hardy Woody Plants from Seed. — McMillan-Browse. P. · Grower Books · 1985 · ISBN 0-901361-21-6 ↩︎Does not deal with many species but it is very comprehensive on those that it does cover. Not for casual reading.
- [20]IUCN Red List of Threatened Species — http://www.iucnredlist.org/ ↩︎A list of plants under threat and facing possible extinction, usually with brief details of the threats and information on habitat.
- [21]Encyclopaedia of Medicinal Plants. — Chiej. R. · MacDonald · 1984 · ISBN 0-356-10541-5 ↩︎Covers plants growing in Europe. Also gives other interesting information on the plants. Good photographs.
- [22]A Modern Herbal. — Grieve. · Penguin · 1984 · ISBN 0-14-046-440-9 ↩︎Not so modern (1930's?) but lots of information, mainly temperate plants.
- [23]Edible and Medicinal Plants. — Launert. E. · Hamlyn · 1981 · ISBN 0-600-37216-2 ↩︎Covers plants in Europe. a drawing of each plant, quite a bit of interesting information.
- [24]The Herb Book. — Lust. J. · Bantam books · 1983 · ISBN 0-553-23827-2 ↩︎Lots of information tightly crammed into a fairly small book.
- [25]Encyclopaedia of Herbs and their Uses. — Bown. D. · Dorling Kindersley, London. · 1995 · ISBN 0-7513-020-31 ↩︎A very well presented and informative book on herbs from around the globe. Plenty in it for both the casual reader and the serious student. Just one main quibble is the silly way of having two separate entries for each plant.
- [26]The Encyclopedia of Medicinal Plants — Chevallier. A. · Dorling Kindersley. London · 1996 · ISBN 9-780751-303148 ↩︎An excellent guide to over 500 of the more well known medicinal herbs from around the world.
- [27]Handbook of the Bach Flower Remedies — Chancellor. P. M. · C. W. Daniel Co. Ltd. · 1985 · ISBN 85207 002 0 ↩︎Details the 38 remedies plus how and where to prescribe them.
- [28]Economic Products of India. Volume 1. — Watt. G. · Government of India: Calcutta. · 1883 ↩︎Although over 100 years old, it still contains a wealth of information on useful plants. Many of the botanical names have been changed since then, so you have to check for up to date names. The book can be downloaded from the Internet.
- [29]CosIng — http://ec.europa.eu/growth/tools-databases/cosing/ ↩︎CosIng is the European Commission database for information on cosmetic substances and ingredients.
- [30]Dictionary of Economic Plants. — Uphof. J. C. Th. · Weinheim · 1959 · ISBN - ↩︎An excellent and very comprehensive guide but it only gives very short descriptions of the uses without any details of how to utilize the plants. Not for the casual reader.
- [31]A Dictionary of Plants Used by Man. — Usher. G. · Constable · 1974 · ISBN 0094579202 ↩︎Forget the sexist title, this is one of the best books on the subject. Lists a very extensive range of useful plants from around the world with very brief details of the uses. Not for the casual reader.
- [32]The Useful Plants of Great Britain. — Johnson. C. P. ↩︎Written about a hundred years ago, but still a very good guide to the useful plants of Britain.
- [33]Plants with a Purpose. — Mabey. R. · Fontana · 1979 · ISBN 0-00-635555-2 ↩︎Details on some of the useful wild plants of Britain. Poor on pictures but otherwise very good.
- [PFAF]Plants for a Future — pfaf.org ↩︎