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What is a Garlic?

Depending on your age, your first thought will probably be to either wrinkle up your nose, or to make the sign of the cross.

For many of the older generation, Garlic is one of those Mediterranean food flavourings that makes you recoil in horror from someone else's breath: whereas the younger generations will immediately think of vampires, and stakes of a different sort.

In fact, the plant family of Allium is a large and varied one, and not all of the members are quite as odoriferous as the one we eat!

The botanical name for edible Garlic is Allium sativum: the Allium part is the classical Latin name for Garlic, although it could also be derived from the Greek αλεω or, as we would spell it aleo, meaning “to avoid”, which has a certain humour to it. As for the “sativum” part, that is Latin again, and simply means “cultivated”.

Garlic, Leek or Onion?

Well, they are all the same family: Leeks are Allium ampeloprasum, onions are Allium cepa, and chives are Allium schoenoprasum - now there's a name to savour. It is pronounced something like shurr-know-PRAY-zum, which is well worth practising as you stand at the chopping board. However, Garlic has a much more pungent aroma than the others, and is the only one whose common form is the small bulblet or clove.

What is Garlic used for?

Although many people enjoy having Garlic to flavour and pep up their food, it is poisonous to both dogs and cats, so don't ever let them clear your plate for you. For humans, though, it has been in use for over 7,000 years: it was known to the Ancient Egyptians, and has been used throughout this time both for food flavouring and for traditional medicine.

In its time, it has been used to treat everything from ringworm to thrush infections: daily use of garlic in the diet has been shown to have a very beneficial effect on the body, especially the blood system and the heart; and modern research is suggesting that it can help with arteriosclerosis, hypertension, and high cholesterol levels. As recently as World War II, Garlic was being used as an antiseptic on open wounds to prevent gangrene.

In the kitchen it really comes into its own, being a staple ingredient of Mediterranean cuisine, as well as being a frequent seasoning throughout its native Asia, Africa, and Europe.

In the garden, Garlic plants are said to be repellent to bunnies, deer and moles, although - as always - most of the success stories are anecdotal. However, it is clear that the strong scent emitted by most of the Allium family will be avoided by the many mammals and small rodents which rely on scent to warn them of predators. It doesn't actually repel the pests, it's just that, like many of us, they don't like to be overwhelmed with any one smell, so they stay away.

Talking of repelling animals, Garlic has been suggested as a way to repel mosquitoes, and there is indeed some truth in the idea. Mosquitoes find their victims by smell: specifically, carbon dioxide and lactic acid, because these chemicals lead them to warm-blooded animals, like us. So breathing and sweating - activities which we just can't avoid doing! - will attract them. Chemicals such as DEET act by masking our own scent, so the mozzies can't find us. Garlic, on the breath or growing in the ground, can also mask our smell, although it might repel more than just the mosquitoes!

Garlic in popular culture

Do we really have to say it? Two bits of firewood, held up in the shape of the cross: a necklace of garlic and a quick snatch at the curtains in time to let in an early sunbeam - ah, the happy days of those early Hammer horror films have a lot to answer for.

The link between vampires and Garlic was started by Bram Stoker in his 1897 novel, “Dracula”, and is based on the folklore belief that garlic repels mosquitoes. The logic is that Dracula, who sucks blood as the mosquitoes do, would also be repelled by Garlic. There are one or two minor flaws in this theory, firstly because garlic may deter mosquitoes but does not repel them completely; secondly, Dracula is the first vampire to suck blood, as the vampire of legend actually sucked up the life force of their victims, more what we would call their spirit, rather than their actual blood; and thirdly because vampires don't really exist.

And of course there is that old folk saying:

“An apple a day keeps the doctor away,
Garlic being stronger, keeps him away longer”

How do you know it's a Garlic?

Generally speaking, the smell will give it away: that lovely whiff which we can all recognise at several paces.

Botanically, Garlics are herbaceous perennials with flowers produced on scapes, which are long, leafless flowering stems, which rise directly from a usually solitary, underground, bulb. These bulbs reform annually at the base of the old bulb, if it is not dug up and eaten: and although they are normally single bulbs, many species of Allium - particulaly our supermarket Garlic - have bulbs which contain a number of segments, which are known as cloves.

The flowers are usually erect and are held in umbels, which are umbrella-like collections of small individual flowers. Each flower has six petal-like tepals, held in two whorls, and once pollinated, they produce round black seeds.

There are 37 cultivars of “Garlic” in our PlantFinder, all but three of which are in the Allium family: but there are over 600 different cultivated sub-varieties of garlic available to keen growers. These are all varieties of Allium sativum, with two subspecies; Allium sativum var ophioscorodon (known as hard-necked garlics), and Allium sativum var sativum (known as soft-necked garlics).

Hard-necked Garlics came first: they have, as the name suggests, a rigid scape (flowering stem) growing upwards from the main bulb, which supports the white or pale pinkish flower head.

Soft-necked Garlics were developed over the centuries as an improvement on the hard-necked types, and they have, instead of a scape, a multi-layered parchment covering the entire bulb, continuing up the neck of the bulb, and forming a soft, pliable stalk suitable for braiding: they don't flower at all, producing just a tuft of narrow foliage. This is the type which is normally sold in supermarkets: soft-necked garlic typically has several layers of cloves surrounding the central portion of the garlic bulb. The outermost layer's cloves are the stoutest; the cloves of the internal layers become smaller closer to the centre of the bulb, and of the several types commonly available, the two most abundant are Silverskin garlics, which have a strong flavour and store well when dried, and Artichoke garlic with a milder flavour and fewer and larger cloves than Silverskin.

Adventurous cooks might be tempted by Elephant garlic (Allium ampeloprasum var. ampeloprasum), which has comically large bulbs, but although it looks like a good buy because it is so large, its flavour is actually quite bland, or maybe “mild” would be kinder, and it is often roasted whole and eaten more as a vegetable than a flavourful herb.

In addition, many Alliums grow as wildflowers - notably Allium ursinum which, strangely, is not known as Bear garlic but instead is called Wild garlic or Ramsons; the commonest narrow-leaved Allium is Allium vineale, also known as Crow garlic or Wild onion; Allium ampeloprasum is Wild Leek, while Allium schoenoprasum (say it to yourself again - shurr-know-PRAY-zum, softly, and with feeling) is now a common wild flower, having escaped from our gardens where it is better known, with its attractive tufted lilac head, as Chives. One more wild garlic of note is Allium triquetrum or Three-Cornered garlic, so named because the stout upright scape is indeed triangular in cross-section: this particular wild flower can become an invasive nuisance, especially if it find its way into a garden.

How to grow Garlic

Garlic is very straightforward to grow: don't try to use up your supermarket leftovers, as they may well have been imported and will not be suited to our climate. Instead, buy a fresh bulb from a local garden centre in early or late autumn - just make sure that you plant them before Christmas, to get the biggest and most flavoursome crop the next year.

As with onions, young Garlic plants are very susceptible to being pulled out of the ground by birds, the little rascals: so you may need to keep an eye on them, pushing any uprooted plants back into the soil, until they are firmly established.

They are ready to be harvested once the leaves have wilted and yellowed, which is usually around June-July time: loosen the soil with a fork and lift them gently, leaving them to dry by spreading them out on netting, or mesh, or old sacks. Once they are fully dry, you can use the leaves to plait them into a rope, which can be hung somewhere cool, dark and dry until you need them.

So what about other Garlics?

Tulbaghia - pronounced Tool-baggy-er - or Society garlic has 20 or more species, two of which are featured in our PlantFinder: T. natalensis and T. violacea, both of which are what you might call “candelabra” plants, as they have a tuft of up to twenty small flowers in an umbel, sitting on top of a long, slender flowering stalk. The leaves and flowers are edible raw, but the bulbous root is more medicinal than culinary, although it may be palatable if cooked. Apparently this plant was given the common name of Society garlic by Dutch settlers to South Africa: it seems they thought it more polite to cook with this plant, which has a more restrained flavour, than to use true Garlic, especially for social occasions.

Then we have the genus Alliaria or “Hedge garlic”. This genus is not an Allium at all, but is in fact part of the mustard family, Brassicaceae. Like many of that family, this plant contains chemicals which smell like garlic when the plant tissues are crushed. Best known is the common weed - sorry, wild flower - Alliaria petiolata, another name which simply trips off the tongue: it is known as Garlic mustard, or even Jack-by-the-hedge.

And it is worth mentioning a couple of species of Allium which are not Garlics at all, but which are nonetheless very popular in modern gardens: Allium christophii and Allium giganteum, both of which have tall, single, pom-pom flowers in shades from white, through blue, to purple, and unless you accidentally crush their foliage, you will never think that they are related to the humble supermarket Garlic.

Why, exactly, does Garlic have to smell so much?

The smell comes from chemical compounds which are produced by all plants in the Allium genus: most of these compounds are derived from cysteine sulfoxides, and they produce the oniony-garlicy smell to a greater or lesser degree. In many Alliums, the smell is released when the foliage is crushed, but in some, such as Ransoms (Allium ursinum) the odour is exuded freestyle, to the point where you know there is some in the area, before you even see it.

The strength or potency of this characteristic smell is greatly affected by the amount of sulphur in the ground where the plants are grown: sulphur is a naturally-occurring mineral, present in most soils to a greater or lesser degree, and apparently if you can arrange sulphur-free growing conditions, you would find that all Allium species would lose their usual pungency: however, as taste is so closely allied to smell, there does not seem to be any point in trying to breed smell-free Garlic.

Instead, it might be worth reading a recent report from The Institute of Food Technologists, who tell us that Garlic is an excellent source of magnesium, vitamin B6, vitamin C, and selenium and is reported to have many health benefits. As we all know, it also contains a high amount of those sulphur compounds, which are responsible for the characteristic odour and flavour of garlic, as well as bad breath. However, a study by the IFT found that drinking milk (full-fat works best) with a garlic-infused meal can reduce the bad breath afterwards. Even drinking milk after the meal can still help, but the study found that drinking it during the meal will have better results. So there you have it - if you want your Garlic, but don't want the bad breath afterwards: drink milk!

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