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This site uses botanical names. Click here for an A to Z common name to botanical name converter.

Ilex aquifolium, holly


Its role as the male god of plant life means it has a mass of folklore but it is best known these days as a Christmas decoration.



Meaning of the Name

Most sources seem to go with a circular definition. ‘Ilex’ is named for ‘Quercus ilex’, the holm oak, which looks like holly and ‘Quercus ilex’ is named for ‘Ilex’ because the holm oak looks like holly. ‘Holm’ is an archaic word meaning ‘island in a river’ so it may be that this was where the plant was first found but the Latin for ‘island’ is ‘insula’.
There are a number of folktales which are very similar in both Greek and Roman history. There is a Roman story of a fugitive asking Apollo where he should settle and being told to build a city where he found people dancing with olive branches on their head.  In the Greek version the people were wearing oak twigs. The Roman city was called ‘Elaeus’, the ‘city of olives’ and one wonders if this corrupted to ilex and became the oak twigs to which the Greek story refers.
‘Folium’ is Latin for ‘leaf’. The ‘aqui’ part is more difficult. It may come from ‘aqua’, ‘water’ perhaps because the shiny leaves appear to be always wet.
‘Aquifolium’ itself is used as a species name in a number of genera where it means ‘looks like holly’.

Common Names and Synonyms

holly, helver, berry holm, aunt mary's tree, poisonberry, Christmas tree, Christ's thorn.

How Poisonous, How Harmful?

Contains saponins. The fruits and leaves contain ilicin, ilexanthin and ilicic acid and a tannin plus cyanogenic glycosides.

The berries are poisonous but a small dose has been used as a purgative. A large dose, of the order of 30 or so berries, can cause nausea, vomiting, diarrhoea and abdominal pain. Effects similar to digoxin have been claimed but there is no clear evidence.


In 1980, a two year old child was reported to have been nauseous for two hours after ingesting two berries.

In another case, twins were suspected of eating holly berries and given an emetic. The resulting vomiting and diarrhoea may be more attributable to the emetic than the berries.

In spite of this low level of reported incidents at least one American book on poison plants states that under no circumstances should holly be brought into the house at Christmas. Considering the millions of household who do bring holly in every year with no resulting poisonings, this seems like a rather overstated fear.

Folklore and Facts

Holly offers a very good example of the problems with much that is written about poison plants. In a book intended to assist parents to identify risks in the garden, the author says that real holly should not be used on Christmas puddings for fear of the berries being eaten and causing poisoning. This is a somewhat extreme position to take since there are, as far as I can ascertain, no reported cases of holly poisoning occurring in this way.

Ilex aquifolium, holly

Ilex aquifolium

To really be helpful to parents it is essential to distinguish between 'poisonous' and 'harmful'.

In pagan ritual, holly symbolised the male god carrying life through the winter in its evergreen leaves. Ivy was the goddess. There are some claims that its use at Christmas relates to the leaves looking like Christ's crown of thorns and the berries looking like blood but these, probably, are just to justify adoption of a pagan ritual. In pagan belief, the holly king rules from midsummer to midwinter when he is replaced by the oak king, until the next midsummer.

A heavy crop of berries is said to be a sign of a hard winter to come. This particular superstition is applied to many berry-bearing plants.

In many parts of the world, the availability of the first food of the new growing season is a cause for celebration often in a highly ritualised way. The Seminole people of North America held a complex ceremony to welcome the new grain. One important aspect was that there must be no danger of the new grain making contact with any of the old and, so, they took a strong purgative called the 'Black Drink’ and composed, largely of a form of holly, Yaupon holly (Ilex vomitoria), in order to ensure that their systems were completely cleansed before they ate the new grain.

In England it is grown close to the house to keep witches away. In Ireland it is grown away from the house so as not to disturb the fairies who live in it.

Grown by druids close to the home to lift winter melancholy.

It keeps away lightning so alcohol vendors would set up their stalls under holly at markets. Thus the association with pub names.

A farmer, accompanied by his wife, his employee and his wife who corroborated his story spoke of the time they bought in some calves which had ringworm, which spread throughout the herd. A farmer friend of his suggested an old remedy: hang boughs of holly around their byre. Within 3 weeks the ringworm had cleared up. They didn't believe it and don't know how it could have worked, but they tell the tale and would do the same again if ringworm struck. This could be an interesting example of what is meant by the Latin phrase ‘post hoc ergo proptor hoc’ meaning, "after this, therefore because of this".