Garlic has a long history in British kitchens, from flavouring Sunday roasts to enriching sauces, soups and stews. It is one of those ingredients that no home cook wants to be without, and its health benefits are celebrated just as much as its culinary value. For many people the idea of growing their own garlic is appealing, and it is natural to look at the bulbs already in the kitchen and wonder whether those from the supermarket can simply be pushed into the soil. The question of whether you can plant supermarket garlic in the UK is asked often, and while the simple answer is yes, the longer explanation is much more nuanced. There are differences between planting cloves bought for cooking and using certified seed garlic, and understanding these differences is key to deciding whether to experiment or to invest in proper planting stock.
How garlic grows
Garlic reproduces from cloves, each of which has the potential to grow into a full bulb containing many more cloves. This makes it an easy crop for beginners to try, as no seeds are needed and the process feels straightforward. Planting is usually done in autumn, when the soil is still workable but cool enough to trigger the period of vernalisation that garlic requires to divide properly into cloves. Cloves planted at this time develop roots before winter and then resume growth in spring. Harvest usually follows in mid to late summer, depending on variety and climate. Planting in spring is also possible, though the bulbs may be smaller if they miss the cold period that encourages splitting.
The appeal of supermarket garlic
Supermarket garlic is always readily available and relatively inexpensive. Many people are tempted to take a clove from a bulb on the kitchen counter and plant it outdoors. Sometimes these cloves sprout and grow, producing green shoots and even bulbs by harvest time. The simplicity of this method is attractive and it seems wasteful to throw away sprouting garlic when it might grow into something useful. For the thrifty gardener the idea of turning kitchen leftovers into a productive crop is satisfying. However, while the concept is appealing, the practical results can be disappointing if you are aiming for large, reliable bulbs.
The problem of imported garlic
Much of the garlic sold in British supermarkets is imported. Spain, China and other warmer countries provide the bulk of what is sold. These varieties are bred for climates very different to the damp and often cold conditions of the UK. When planted here, the cloves may sprout but fail to divide properly, resulting in small bulbs known as rounds. These can still be eaten but they lack the quality and storability of properly grown bulbs from varieties suited to local conditions. Imported garlic may also struggle to cope with frost, heavy rain or the fluctuating temperatures of a British winter, leading to rot or stunted plants.
Disease risk from supermarket bulbs
Perhaps the most serious risk in planting supermarket garlic is disease. Bulbs grown for eating are not certified as disease free, and may carry hidden infections. White rot is one of the most feared diseases of garlic and other alliums. It causes plants to yellow, wilt and rot at the base, leaving the soil contaminated for decades. Once white rot is present, it becomes nearly impossible to grow garlic, onions, leeks or shallots in that area again. Introducing this problem through supermarket garlic can devastate a garden and make future harvests impossible. Other fungal diseases and viruses may also be introduced, which is why garden centres and specialist suppliers emphasise the use of certified seed garlic.
The difference between seed garlic and supermarket garlic
Seed garlic may look the same as supermarket bulbs, but it has been produced with a very different purpose. Certified seed garlic is tested to ensure it is free from disease, bred for specific climates and chosen for reliable yields. In the UK, suppliers provide varieties of both hardneck and softneck garlic that are suited to local conditions. Hardneck types produce scapes, edible flowering stems that can be harvested in early summer, while softneck types tend to store for longer after harvest. Both groups offer varieties that thrive in British soil and weather, giving gardeners a far higher chance of success than relying on imported supermarket bulbs.
Sprouting garlic in the kitchen
Cloves that sprout while sitting in the kitchen are often the trigger for trying to plant supermarket garlic. These green shoots indicate that the bulb is still alive and capable of growing. Planting them outdoors may produce some growth, but results are unpredictable. An alternative is to plant them in pots indoors and use the shoots as garlic greens, which can be snipped and used like chives or spring onions. This method is safe, avoids the risk of soil disease and provides a quick harvest for the kitchen, even if it does not yield full bulbs.
The risk of white rot explained further
White rot deserves particular attention because of its long lasting consequences. It thrives in cool, damp soil, exactly the conditions often found in the UK. The fungus produces sclerotia, tiny structures that can survive for up to 30 years in the soil even without host plants. Once introduced, these can infect any future allium crops, making it impossible to grow onions, leeks, shallots or garlic in that plot. The disease spreads easily on tools, shoes or in compost, so once present it can be difficult to contain. This is why so many experienced gardeners advise against planting supermarket garlic directly in garden soil. The potential cost to long term productivity far outweighs the small saving on planting stock.
Economic arguments
At first glance, supermarket garlic appears cheaper than seed garlic. A bulb may cost less than a pound, while seed garlic bulbs often cost several pounds each. However, when considering yield, quality and reliability, the difference is not so clear. Certified seed garlic produces large, healthy bulbs that can be stored for months and replanted in future seasons. Supermarket garlic may produce small or misshapen bulbs, or even fail entirely, making the initial saving meaningless. Over time, investing in proper seed garlic results in larger harvests and fewer risks, ultimately offering better value.
Growing conditions in the UK
Garlic prefers a sunny site with free draining soil. Heavy clay soils should be improved with compost or grit to prevent waterlogging, which can cause cloves to rot. Autumn planted cloves benefit from the cold of winter, which stimulates proper clove division. Spring planted cloves grow quickly but may produce smaller bulbs. Watering during dry spells and keeping weeds under control are important for strong growth. These conditions are easier to meet with varieties bred for the UK, while supermarket bulbs bred for Mediterranean climates may not respond well to British weather.
Container growing as a compromise
For those who want to experiment with supermarket garlic, growing in containers offers a safer compromise. Planting cloves in pots filled with fresh compost avoids the risk of contaminating garden soil with disease. Containers should be placed in a sunny spot and watered regularly, but not left waterlogged. Even if the bulbs do not develop fully, you can harvest the greens and rounds without worrying about long term soil damage. This approach allows for experimentation while keeping main growing beds safe for future crops.
Harvesting and storing garlic
Garlic planted in autumn is usually ready to harvest by mid summer, when the leaves begin to yellow and fall over. The bulbs should be carefully lifted, dried in a well ventilated place and stored in a cool, dry environment. Softneck varieties often store for months, sometimes lasting into the following spring, while hardneck types are best used within a few months. Proper curing ensures good flavour and prevents rot. Supermarket garlic, even if it grows successfully, may not store as well as certified varieties, making the harvest less useful for long term use.
Experimentation versus reliability
Ultimately, whether to plant supermarket garlic in the UK depends on what you hope to achieve. If you are experimenting, want to use sprouting cloves rather than waste them, or are happy with a small harvest of greens and rounds, it can be worth trying in containers. If your goal is to produce large, healthy bulbs for cooking and storage, certified seed garlic is the more reliable choice. Understanding the risks of disease, the importance of climate suitability and the difference in long term value helps gardeners make informed decisions about which path to take.
Conclusion
So, can you plant supermarket garlic in the UK? Yes, but with significant caveats. Supermarket garlic may sprout and grow, but it is not bred for British conditions and may not produce good bulbs. Worse, it can carry diseases like white rot that can ruin soil for decades. The safest approach for experimentation is to grow supermarket garlic in containers, harvesting greens or rounds without risking the health of garden beds. For consistent success, however, certified seed garlic remains the best option, ensuring disease free planting stock, varieties suited to the UK climate and large, flavoursome bulbs. For the serious gardener, investing in proper planting stock always pays off in the long run.
