How to grow garlic in the UK: planting, care, harvest and storage

Garlic is one of the simplest edible crops to start in a British garden. Buy a named garlic variety intended for planting, split the bulb into individual cloves and plant each clove with its pointed end upwards. Give it a sunny position and soil that drains well. Garlic planted in autumn grows through the colder months and is usually harvested the following summer, once its leaves start to yellow.

There is one important difference between garlic and many spring vegetables: a period of cold helps the plant form a proper divided bulb. That is why autumn planting is the usual choice in Britain, although some varieties can be planted in late winter or spring.

Choose the right garlic to plant

Garden-centre garlic for planting is a better choice than a bulb from the supermarket. The Royal Horticultural Society advises buying named planting varieties because supermarket garlic may be poorly suited to British conditions and can carry biosecurity risks.

The two familiar groups are hardneck and softneck garlic. Hardneck types generally produce fewer, larger cloves and often develop a flowering stalk known as a scape. Their flavour can be strong, but their storage life is usually shorter. Softneck garlic tends to contain more tightly packed cloves, rarely flowers in ordinary conditions and generally stores longer.

Choose according to what you will actually do with the harvest. If you want large cloves for cooking and will use the crop relatively quickly, hardneck can be appealing. If you hope to hang or store garlic for many months, look at a suitable softneck variety. Check the packet for its planting and cropping windows rather than relying on the broad group name alone.

When to plant garlic in the UK

Mid-autumn to early winter is the usual planting period. The cloves establish roots in cool soil, then produce their main leafy growth as the weather improves. Most varieties benefit from roughly one or two months of cold conditions for good bulb development, although requirements vary.

Spring planting is possible if you buy a variety sold for it. Don't expect cloves planted late in spring to perform identically to autumn-planted garlic. The length of the growing season and exposure to cold can affect whether the finished bulb divides properly.

If the ground is extremely wet in November, resist the urge to push cloves into mud simply to keep to a calendar date. Garlic dislikes sitting in persistently wet soil. In areas with heavy winter rainfall, consider starting cloves in modules under cover and planting them outside in spring.

The best planting date depends on the variety, soil and local conditions. For a Lancashire allotment with waterlogged winter clay, the correct method may differ from a sheltered, freely draining bed in southern England.

Find a suitable growing position

Garlic needs a bright, open site. Give it the sunniest reasonable part of the vegetable plot, away from tall crops that will cast heavy shade as spring progresses.

Drainage matters especially during the winter. If your soil is heavy, improve its structure in advance with well-rotted organic matter, or use a raised bed. Avoid adding fresh manure directly around garlic cloves. Test very acidic soil rather than applying lime on guesswork: the RHS notes that garlic struggles where soil pH is below about six.

Remove weeds before planting. Garlic leaves are narrow and cannot shade out vigorous weeds the way a spreading pumpkin or courgette can. Preparing the bed thoroughly now saves you disturbing the roots and developing bulbs later with a hoe.

You can plant through a suitable weed-suppressing covering or mulch between rows, but it still needs to allow the shoots to emerge and the soil to drain. The goal is a tidy, manageable bed, not to seal the cloves into wet conditions.

How to plant garlic cloves step by step

1. Separate the cloves. Break apart a healthy planting bulb gently. Leave the papery skin around each clove; don't peel it as if you were cooking.
2. Select sound cloves. Set aside pieces that are obviously damaged or showing mould. The larger, healthy cloves are usually easier to handle and establish.
3. Point the tip upwards. Each clove has a flatter basal end where the roots form. That end goes down into the soil, with the pointed shoot end facing up.
4. Plant to the correct depth. Following RHS guidance, place each clove so its tip is roughly 2.5cm below the soil surface. Do not bury them excessively deeply in heavy, wet ground.
5. Leave room for the bulbs. Space cloves about 15cm apart, with rows around 30cm apart. This leaves enough space to reach weeds and lift the mature crop.
6. Close the planting hole gently. Firm the soil around the clove without crushing it. Water only as necessary for the actual soil conditions.

Birds sometimes pull up newly planted cloves. If that happens in your garden, protect the bed with properly secured fleece or suitable mesh until the cloves root and become established. Check underneath occasionally rather than leaving the cover forgotten.

A simple label with the variety and planting date is useful, especially if you're comparing hardneck and softneck types. Several months will pass before the finished bulbs tell you whether the choices suited your plot.

Growing garlic in pots and modules

You don't need a full vegetable bed. Garlic can grow in a container, provided the roots have enough compost and the pot drains freely. The RHS advises using a container at least 25cm deep and keeping the usual spacing between cloves, rather than filling every available centimetre with planting material.

Use good-quality peat-free multi-purpose compost and make sure excess rainwater can escape. Pots may need watering more often than ground-grown garlic in dry weather, but they are also vulnerable to sitting in wet compost through winter. A sheltered spot outdoors is generally more suitable for growing a bulb crop than an overheated kitchen windowsill.

Modules provide another option, especially where garden soil is waterlogged. Put one clove in each cell, covering the tip with around 2.5cm of compost. Keep the trays in an unheated greenhouse, cold frame or other sheltered, cool position where they will not remain sodden. Plant the rooted cloves out in spring without unnecessarily pulling their roots apart.

A pot-grown plant is still a garlic plant with a normal seasonal growing cycle. Don't assume that keeping it indoors all year will produce the same crop as allowing it the appropriate cool growing period.

Caring for garlic during spring and early summer

Once shoots appear, your main jobs are weeding, occasional watering and checking the leaves. Garlic doesn't usually need constant intervention. It needs an open position where sunlight can reach the leaves and the bulbs can swell.

Water during prolonged dry spells in spring and early summer, especially on light soils or in containers. Don't automatically water every day: check moisture below the surface. As bulbs mature and the foliage begins to yellow, reduce watering rather than soaking nearly ready bulbs.

Remove weeds by hand near the plants. A hoe can damage developing bulbs that are closer to the surface than you realise. Mulch may save some of that work, but keep an eye on slugs and on excessively damp conditions around the plant bases.

Hardneck varieties often send up a firm flower stalk that curls above the leaves. Cut the scape while it is young if your aim is a good storage bulb. The RHS recommends removing flower stalks because flowering can take energy away from bulb development. Young scapes are edible and can be cooked in much the same way as other garlicky vegetables.

How to tell when garlic is ready to lift

Garlic is commonly harvested in late spring or summer, depending on the planting time and variety. Autumn-planted types usually finish earlier than spring-planted ones. The leaves give the most useful clues.

As the bulb matures, the foliage begins to turn yellow and die back. Don't wait until every leaf has completely disappeared. Garlic that remains in the ground too long can split open, which reduces how well it stores. Nor should you lift an entire bed just because one slightly stressed plant has a yellow leaf.

Loosen the soil around a test plant carefully with a fork, lifting from a little distance so you don't spear the bulb. Examine whether the bulb has developed properly. If the remaining plants look similar and the crop is ready, lift the rest gently and avoid bruising them.

Treat the bulbs as food you hope to store, not as stones to knock clean against the edge of a spade. Damaged bulbs are better used promptly rather than mixed into a long-storage batch.

Drying and storing the harvest

Freshly lifted garlic needs time to dry before long-term storage. Spread the bulbs in a single layer where air can circulate. A sheltered, well-ventilated greenhouse or dry shed can work, provided it isn't excessively hot. The RHS advises avoiding temperatures above 30°C during initial drying.

Drying may take two to four weeks, depending on weather and conditions. The foliage should feel dry and rustle rather than remain soft and green. Once dried, trim the leaves if you aren't keeping the stems for hanging, and store sound bulbs in a cool, dry, ventilated place.

Hardneck garlic often keeps for around four to six months; suitable softneck varieties may keep considerably longer. Treat those periods as guidance rather than a guarantee. Inspect stored bulbs occasionally and use any damaged or deteriorating ones first.

Don't seal incompletely dried bulbs into airtight containers. Trapped moisture encourages problems after all your work growing them. The aim is dry bulbs with airflow, away from places where condensation forms.

Common garlic problems

A bulb with one large clove: Some plants form a single round bulb instead of separating into numerous cloves. Inadequate cold exposure can be one cause. Check the variety and planting season before trying again; it doesn't necessarily mean the garlic is unusable.

Cloves emerging from the flower stem: These are sometimes called top sets. Unusual weather and flowering can contribute, and the small cloves can still have culinary uses. Harvest them separately rather than mistaking them for the main underground crop.

Bulbs rotting before harvest: Look at drainage and watering. Planting into cold, waterlogged soil and continuing heavy watering as bulbs mature can make problems worse. Move future crops to better-drained ground or try modules and spring transplanting.

Leaf problems: Garlic shares several pests and diseases with onions and leeks, including allium leaf miner, onion white rot and rust. If leaves are badly marked, distorted or declining, identify the actual problem before applying a treatment or moving affected material around the plot.

Small bulbs: Check whether the plants had adequate sunlight, enough growing time and sufficient spacing. A late planting, competing weeds or a difficult season may have limited development. Feeding a mature bulb heavily at the end of the season will not replace months of lost growing time.

Common questions

Can I plant a clove from a supermarket garlic bulb?

It may sprout, but that doesn't make it the best planting material. The RHS recommends named varieties from gardening suppliers because supermarket garlic may be unsuited to UK conditions and could introduce diseases.

Should I peel garlic before planting?

No. Separate the individual cloves but leave their dry protective skins in place. Plant with the flat rooting end down and the pointed tip upwards.

Can garlic survive a UK winter?

Appropriate varieties are usually planted in autumn precisely because they benefit from a cool period. What they dislike most is a prolonged spell in poorly drained, saturated soil.

Sources and further reading

• Royal Horticultural Society — How to grow garlic. Planting seasons, clove spacing, watering, scapes, lifting and storage.
• Royal Horticultural Society — Garlic plant profile. Soil and site preferences, propagation and common problems.