How to Grow Garlic

A member of the onion family, this staple of Mediterranean cooking is simple to grow in a warm sunny site with well-drained soil. It’s grown from cloves, which are best planted in autumn, and is ready to harvest the following year, in late spring and summer.

Hardy, sun-loving garlic is an increasingly popular crop, as it needs minimal maintenance, takes up relatively little space and produces reliable harvests. Started off from cloves rather than seed, it needs no cosseting. It usually requires a spell of cold to form a good bulb, so is generally planted in autumn to overwinter outdoors.

Simply keep weeds at bay and water during prolonged dry spells, and you’ll be harvesting your own garlic from late spring onwards, depending on the variety. Garlic stores well for several months, so you can grow plenty to use as needed, and benefit from garlic’s many health-boosting properties.

Garlic is grown from cloves – the small individual segments in a bulb of garlic. These should be named varieties bought from a garden centre or mail-order supplier. It is not recommended to plant garlic bought from the supermarket as it may be unsuitable for the British climate, giving disappointing results. There are also biosecurity

Measures aimed at preventing the spread of potentially harmful organisms (pests, diseases or invasive species) into the environment. These include sourcing plants responsibly, quarantining new plants and practising good garden hygiene. risks (such as introducing diseases) associated with planting supermarket-bought bulbs

These are fleshy, rounded, underground storage organs, usually sold and planted while dormant. Examples include daffodils, tulips, hyacinths, lilies, onions and garlic. The term is often used to cover other underground storage organs, including corms, tubers and rhizomes. .

There are two main types of garlic – hardneck and softneck.

Hardneck garlic:

• Produces bulbs with fewer, larger cloves
• Has a stronger flavour
• Stores well for about four to six months
• More prone to bolting
  When a vegetable plant starts flowering and forming seeds, often prematurely, making the crop unusable – salad leaves may turn bitter and root crops fail to swell. Adverse weather or changes in day length can cause bolting in a wide range of vegetables, including lettuces, onions , carrots and otheer root crops. (flowering), which can lead to a smaller bulb that won’t store

Softneck garlic:

• Produces smaller, more tightly packed cloves
• Stores for longer – if planted in autumn it will keep well into the following winter, if planted in spring it will keep until the middle of the following spring
• Unlikely to bolt
  When a vegetable plant starts flowering and forming seeds, often prematurely, making the crop unusable – salad leaves may turn bitter and root crops fail to swell. Adverse weather or changes in day length can cause bolting in a wide range of vegetables, including lettuces, onions , carrots and otheer root crops. , except in poor growing conditions

Within these two categories, there are many varieties to choose from, with different harvesting times, storage lengths, bulb sizes and flavours. Look in particular for varieties with an RHS Award of Garden Merit (AGM), which shows they performed well in RHS trials – see our list of AGM fruit and veg (135kB pdf) and our Recommended Varieties below.

Elephant garlic (Allium ampeloprasum) is often sold as garlic, but is actually more closely related to leeks. It produces a big bulb with a small number of very large cloves, which have a mild flavour. It needs a long, warm growing season

The period of time when an individual plant is in active growth. This will depend on the local climate and light levels, and can vary between different plants, although it is broadly from spring to autumn. to produce a good crop and is best planted in October.

Elephant garlic sometimes doesn't divide into cloves, producing just a large single-clove (solo) bulb. Early planting often reduces the occurrence of solo bulbs. You can either eat solo bulbs or re-plant them the following autumn – they will usually go on to produce a multi-clove bulb.

What and where to buy

Named garlic varieties are widely available in autumn and spring, in garden centres and online, with several specialist suppliers offering a particularly wide choice.

Recommended Varieties

‘Arno’

An attractive softneck variety with ivory-white skin covering pinkish cloves. Stores well.

Read more

'Cristo' AGM

A softneck variety with pure white bulbs. Has a strong flavour but a light aroma. Stores well.

Read more

'Germidour' AGM

A well known and reliable softneck variety. Large bulbs with a fairly mild, but rich flavour.

Read more

‘Solent Wight’ AGM

A softneck variety well adapted to the British climate. The bulbs store well.

Read more

Showing 3 out of 4 recommended

Show more

Garlic likes a sunny site with free-draining soil. Wet soil can make garlic more prone to disease, particularly if planted in autumn. If your soil is heavy and wet over winter, it’s better to start garlic off in modules

Small individual cells, usually in a tray, used for sowing seeds. The resulting seedlings can be transplanted with minimal root disturbance. before planting out in spring – see Planting in modules below. Garlic doesn’t like acid soil (below pH

This describes how acid or alkaline soil is, and is expressed as a number between 0 and 14. Soil with a pH of 7 is neutral, an acid soil has a lower value, and an alkaline soil has a higher one. Most plants grow best in soil that’s within a specific pH range, so it’s useful to know your soil’s pH. Testing kits are easy to use and widely available in garden centres and online. 6.5), but you can reduce acidity by applying limein autumn or winter – you can carry out a simple pH test to check if this is necessary.

Prior to planting, remove any weeds, then improve the soil’s structure, moisture retention and nutrient levels by digging in organic matter. Apply about two bucketfuls of well-rotted (not fresh) manure or homemade garden compost every square metre/yard. Alternatively, if you're practicing no-dig, mulch

Mulch is a layer of material, at least 5cm (2in) thick, applied to the soil surface in late autumn to late winter (Nov-Feb). It is used to provide frost protection, improve plant growth by adding nutrients or increasing organic matter content, reducing water loss from the soil, for decorative purposes and suppressing weeds. Examples include well-rotted garden compost and manure, chipped bark, gravel, grit and slate chippings. the soil with organic matter ahead of planting directly into the mulch.

To reduce the need for weeding later, you could cover the soil with biodegradable

Anything that can be decomposed by fungi, bacteria and micro-organisms, so it doesn’t persist indefinitely in the environment. Biodegradable plastics are usually made from plants, such as bamboo, rather than fossil fuels. Ideally, products that claim to be biodegradable should break down quickly and leave nothing harmful behind. However, they may need specific conditions in order to biodegrade successfully or may produce greenhouse gases such as methane in the process. weed-suppressing membrane, then plant the cloves through slits.

Planting in the ground

Garlic is usually planted from mid-autumn to early winter, as it needs a period of cold – most varieties need one to two months at 0–10°C (32–50°F) for good bulb development. However, some varieties are suitable for planting in late winter and early spring.

Once you’ve prepared your planting site (see above), carefully split your garlic bulbs

These are fleshy, rounded, underground storage organs, usually sold and planted while dormant. Examples include daffodils, tulips, hyacinths, lilies, onions and garlic. The term is often used to cover other underground storage organs, including corms, tubers and rhizomes. into individual cloves. Be sure to plant them the right way up, with the flat end downwards and the pointed end upwards. Space the cloves 15cm (6in) apart, with the tip 2.5cm (1in) below the soil surface. In light soil, deeper planting can produce larger bulbs, but don’t plant deeply in heavy soil. Space rows 30cm (1ft) apart.

Birds sometimes pull up newly planted cloves, so cover with platic-free netting or horticultural fleece

A soft, fibrous, translucent material laid over or around plants hastening their growth and protecting them against weather and pests. Heavier grades of fleece give about 2°C of protection from frost. It is usually used without supporting hoops. until well rooted in.

Planting in modules

If your soil is heavy and/or wet over winter, start garlic off in modules

Small individual cells, usually in a tray, used for sowing seeds. The resulting seedlings can be transplanted with minimal root disturbance. in autumn. Keep them in an unheated greenhouse, cold frame

Cold frames are glaze box-like structures made from brick or wood with a  hinged or removable, glazed, sloping lid. Useful to protect plants from cold weather over winter or acclimatise (harden off) young plants in spring and provide extra warmth for tender crops in summer. or a sheltered outdoor location over winter, then plant them out in spring.

• Partly fill a modular tray with peat-free multi-purpose or soil-based compost
  Soil-based compost is a potting compost that includes sterilised soil/loam in the mix. As loam contains sand, silt and clay, it does not rot down like organic materials, so adding soil/loam to compost ensures it is longer lasting – it is often used for shrubs in pots and will last 3–4 years without the need to be replaced.
• Insert one clove into each module, so the tip of the clove is covered by about 2.5cm (1in) of compost
  Can refer to either home-made garden compost or seed/potting compost: • Garden compost is a soil improver made from decomposed plant waste, usually in a compost bin or heap. It is added to soil to improve its fertility, structure and water-holding capacity. Seed or potting composts are used for growing seedlings or plants in containers - a wide range of commercially produced peat-free composts are available, made from a mix of various ingredients, such as loam, composted bark, coir and sand, although you can mix your own.
• Place in a cool location protected from excess rain and the harshest winter weather – a well-ventilated cold frame is ideal
• Keep the compost slightly moist but not wet
• Plant out in spring, into prepared ground (see above), 15cm (6in) apart

Planting in containers

If you have soil that doesn't drain well or you're limited for soil space, it's possible to grow garlic in a container using a peat-free multi-purpose compost

Can refer to either home-made garden compost or seed/potting compost: • Garden compost is a soil improver made from decomposed plant waste, usually in a compost bin or heap. It is added to soil to improve its fertility, structure and water-holding capacity. Seed or potting composts are used for growing seedlings or plants in containers - a wide range of commercially produced peat-free composts are available, made from a mix of various ingredients, such as loam, composted bark, coir and sand, although you can mix your own. . Pots should be at least 25cm (10in) deep, their width and length will determine how many cloves you can plant – aim for the same spacing and depth used when planting in the ground (see above). Compost in containers can dry out quickly, so be prepared to regularly check if you need to water.

Garlic needs little maintenance, apart from watering during prolonged dry spells and weeding to prevent overcrowding. Also snip off any flower stems that start to form.

Watering

To improve bulb size, water garlic during dry spells in spring and early summer. However, don’t water once the bulbs

These are fleshy, rounded, underground storage organs, usually sold and planted while dormant. Examples include daffodils, tulips, hyacinths, lilies, onions and garlic. The term is often used to cover other underground storage organs, including corms, tubers and rhizomes. are large and well formed, as this could encourage rotting – yellowing foliage is a sign that the bulbs are reaching this stage of maturity. Try to avoid wetting the leaves when watering, as this can encourage fungal problems.

Weeding

Garlic needs full sun, so weed regularly to ensure plants don’t get shaded. This is best done by hand, as hoeing

Hoes are multi-purpose tools for weeding (especially between rows of veg), loosening the soil surface, making seed drills, earthing up plants, and more. There are various types with different shaped blades. Hoeing to remove weeds is best done on a warm, dry day, so you slice easily through weed stems just below the surface. risks damaging the developing bulbs

These are fleshy, rounded, underground storage organs, usually sold and planted while dormant. Examples include daffodils, tulips, hyacinths, lilies, onions and garlic. The term is often used to cover other underground storage organs, including corms, tubers and rhizomes. . Alternatively, to reduce the need for weeding, consider planting through a biodegradable

Anything that can be decomposed by fungi, bacteria and micro-organisms, so it doesn’t persist indefinitely in the environment. Biodegradable plastics are usually made from plants, such as bamboo, rather than fossil fuels. Ideally, products that claim to be biodegradable should break down quickly and leave nothing harmful behind. However, they may need specific conditions in order to biodegrade successfully or may produce greenhouse gases such as methane in the process. weed-suppressing membrane or lay a mulch

Mulch is a layer of material, at least 5cm (2in) thick, applied to the soil surface in late autumn to late winter (Nov-Feb). It is used to provide frost protection, improve plant growth by adding nutrients or increasing organic matter content, reducing water loss from the soil, for decorative purposes and suppressing weeds. Examples include well-rotted garden compost and manure, chipped bark, gravel, grit and slate chippings. , such as cardboard, between rows.

Removing flowers

Remove any flower stems as soon as they start to form, otherwise the plant’s energy will go into producing the flower rather than swelling the bulb. It also means the bulb won’t store well. If picked young, while the flower is still in bud

A bud is a small, undeveloped shoot that contains the potential for new growth. Buds are typically found on stems, where they can be apical (found at the tip) or axillary (found between leaf axils) and may develop into leaves, shoots or flowers. , the flower stalks (scapes) are delicious sautéed, barbecued or roasted.

While the bulbs

These are fleshy, rounded, underground storage organs, usually sold and planted while dormant. Examples include daffodils, tulips, hyacinths, lilies, onions and garlic. The term is often used to cover other underground storage organs, including corms, tubers and rhizomes. are still growing, you can harvest a few of the green leaves to use as a garnish or in salads. You may sometimes find cloves form on the stalk (known as ‘top sets’) due to changeable weather in spring – these can be used as you would normal garlic cloves. If a flower stem starts to form, this can be cooked and eaten too.

Garlic bulbs are ready to harvest once the leaves have turned yellow. Autumn-planted garlic is ready from late spring to early summer and spring-planted garlic is ready from mid-summer to early autumn. Try not to delay harvesting, as bulbs that are lifted late tend to open up and have a shorter storage life. Carefully dig up the bulbs with a fork. Handle them gently, as bruising also reduces their storage potential.

To prepare garlic bulbs

These are fleshy, rounded, underground storage organs, usually sold and planted while dormant. Examples include daffodils, tulips, hyacinths, lilies, onions and garlic. The term is often used to cover other underground storage organs, including corms, tubers and rhizomes. for storing, dry them off thoroughly in a single layer in the sun – a well ventilated greenhouse is ideal, but avoid excessive heat (above 30°C/86°F). Alternatively, place them in a dry, well-ventilated shed.

Initial drying takes two to four weeks, depending on the weather. Once the foliage is dry and rustling, cut it off and store the bulbs in a cool, dry place at 5–10°C (41–50°F), where further drying will take place. Garlic can usually be stored for several months. Hardneck varieities can store well for four to six months. Softneck varieties store for longer, potentially up to a year.

Garlic is usually trouble-free in good growing conditions. However, it can potentially be affected by similar problems to onions and leeks (see Common problems, below). The following issues, related to growing conditions or harvesting, could also arise:

• Cloves forming on the stem – this is usually due to adverse weather, such as fluctuating temperatures in spring. Called ‘top sets’, the cloves can be used in the normal way
• Bulbs
  These are fleshy, rounded, underground storage organs, usually sold and planted while dormant. Examples include daffodils, tulips, hyacinths, lilies, onions and garlic. The term is often used to cover other underground storage organs, including corms, tubers and rhizomes. not dividing into cloves – this is usually the result of insufficient cold weather over winter
• Flowering ( bolting
  When a vegetable plant starts flowering and forming seeds, often prematurely, making the crop unusable – salad leaves may turn bitter and root crops fail to swell. Adverse weather or changes in day length can cause bolting in a wide range of vegetables, including lettuces, onions , carrots and otheer root crops. ) – hardneck garlic readily produces flower stems, which should be removed as soon as they appear and can be used in stir-fries. Softneck garlic occasionally produces flower stems due to poor growing conditions, such as high temperatures or drought
• Split bulbs – this can happen if the crop was harvested late
• Green cloves – usually due to shallow planting. They can be used as normal, but are unlikely to store well

Common Problems

Allium leaf miner

Allium leaf mining fly was first detected in Britain in 2002, it has become widespread in England and parts of Wales. The larvae bore into the stems a...

Read more

Leek rust

Leek rust is a common fungal disease of leeks and garlic, but also affects onions and chives. The fungus causes bright orange, raised spots (pustules)...

Read more

Onion downy mildew

Onion downy mildew is a disease of onions and related crops that damages foliage and bulbs, resulting in loss of yield or even a complete failure of w...

Read more

Onion white rot

White rot is a serious fungal disease of onions, garlic and leeks causing yellowed, wilting foliage and decay of the roots and bulb. It may persist in...

Read more

Leek moth

Leek moth was mainly found in southern England but it is spreading north, it is not as frequently seen as the allium leaf mining fly. The caterpillars...

Read more

Onion fly

The maggots of onion fly can damage the roots and bulbs of onions and some related plants, sometimes killing seedlings.

Read more

+1

Showing 3 out of 6 recommended

Show more