edible gardening
When to plant garlic in the UK — autumn planting guide
Plant garlic in mid-October across most of the UK for harvest next July. Hardneck for the north, softneck for the south. Full regional autumn calendar.
When to plant garlic in the UK — autumn planting guide
Garlic is the upside-down crop in the British vegetable garden. While almost everything else goes in the ground in spring for a same-year harvest, garlic is planted in autumn, sleeps through the UK winter, and is dug up around 9 months later — usually right before the tomato crop hits its stride. Get the timing right and a single clove turns into a full head of 8-12 cloves. Get it wrong and you end up with marbles. This guide is the UK regional autumn calendar, the hardneck vs softneck call, and the spring-planting backup plan for gardeners who missed the autumn window.
Personal reminder: Add your postcode to Growli and the app pings you in your specific planting week — tied to your local first-frost forecast from Met Office data, not a generic chart date.
Why autumn planting beats spring in the UK
Garlic is biennial in behaviour. It needs a cold period (vernalisation) of 6-8 weeks at temperatures below about 4°C to trigger bulb formation. The UK winter delivers that for free almost everywhere — but only if you get the cloves in the ground in time to use it.
Equally important: bulb size is set by root mass going into winter. Cloves planted 4-6 weeks before the first hard frost develop a strong root system in cool autumn soil while top growth stays minimal. Those roots resume in early spring and fuel the leaf burst that determines next summer's bulb size. Plant too late and the roots never establish before the ground freezes; plant too early and the green tops emerge, get knocked back by frost, and the plant wastes energy regrowing.
The window is forgiving — anywhere from 4 to 6 weeks before your area's first hard frost works. For most of the UK that means mid- to late October.
UK regional timing
| UK region | First hard frost (avg) | Plant cloves | Mulch by |
|---|---|---|---|
| Channel Islands, south Cornwall, south Devon | Late November / December | Mid- to late October | Optional — mild winters |
| Southern England (London, Bristol, Brighton, Kent) | Mid- to late November | Mid-October | Late November |
| Wales (mostly mild, variable in the mountains) | Mid-November | Mid-October | Late November |
| Midlands (Birmingham, Manchester) | Early to mid-November | Early to mid-October | Mid-November |
| Northern England (Yorkshire, Lake District) | Late October / early November | Late September to early October | Late October |
| Scotland (lowlands — Edinburgh, Glasgow) | Late October | Late September | Mid- to late October |
| Scotland (highlands / islands) | Mid-October | Mid-September or wait for spring | Optional |
| Northern Ireland | Early to mid-November | Early to mid-October | Mid-November |
A second UK window opens in late February to early March for spring-planted varieties (some cultivars are sold specifically for spring sowing, others — including Solent Wight — handle both autumn and spring planting). Spring-suitable softnecks such as Solent Wight, Cristo AGM, and Germidour AGM crop alongside autumn ones in mid-July but produce slightly smaller bulbs.
How to count back from your first-frost date
The rule is simple: plant 4-6 weeks before your first hard frost. Use the chart above for your region, or look up your specific postcode hardiness rating for a finer estimate.
Worked example: Bristol, first hard frost typically mid-November. Count back 4-6 weeks: mid-October planting window. Plant by 20 October, mulch with straw or composted bark by mid-November once the first frost is forecast.
Hardneck vs softneck — which to choose in the UK
Garlic splits into two subspecies, and the choice changes both your planting window and your harvest.
Hardneck garlic (Allium sativum var. ophioscorodon)
- Best in Scotland, northern England, the Midlands, and Wales — needs a real cold winter to bulb properly.
- Produces scapes (curly flower stalks) in early summer — snap them off and eat them sautéed.
- Larger, easier-to-peel cloves (typically 6-10 per bulb).
- Stores 4-6 months.
- Stronger, more complex flavour.
- UK varieties: Lautrec Wight (the UK-bred classic), Carcassonne Wight (RHS Award of Garden Merit), Chesnok Red.
Softneck garlic (Allium sativum var. sativum)
- Best in southern England, the Channel Islands, and southern Wales — tolerates milder UK winters and crops earlier.
- No scapes.
- More cloves per bulb (10-20), smaller individual cloves.
- Stores 8-12 months — this is the supermarket-style garlic.
- Milder flavour, plaitable necks (the strings of garlic at farmers' markets).
- UK varieties: Solent Wight (the UK-bred mainstay, RHS Award of Garden Merit), Picardy Wight, Mersley Wight (selected from Solent Wight stock for larger cloves and 10-month storage), Iberian Wight (Spanish-origin softneck, matures up to a fortnight earlier).
In the overlap zone (the Midlands, southern Wales, central England) plant both — you get the flavour of hardneck and the storage life of softneck. The Isle of Wight Garlic Farm has bred most of the UK-suited cultivars and is the canonical UK source for seed garlic by post.
Spring planting — the UK backup
Spring planting is a legitimate fallback, not a failure mode. Use it if:
- You missed the autumn window (life got busy, ground was waterlogged in October).
- You live in the Scottish highlands where some autumn plantings get killed by sustained frost.
- You only have heavy clay soil that sits wet through winter.
The spring rule: plant as soon as the ground is workable — late February in Cornwall and the south coast, early to mid-March across most of England and Wales, late March in Scotland. Use cultivars sold for spring planting (Cristo AGM, Germidour AGM, Marco, or Solent Wight, which suits both seasons), or pre-chill autumn cloves at around 4°C for 6-8 weeks in the fridge to simulate the missed winter.
Expect smaller bulbs. Spring-planted garlic typically produces bulbs 30-50% smaller than autumn-planted. Cloves may not fully differentiate, so some heads come out as single rounds — still useful in cooking, just not as pretty. Harvest happens at around the same time (mid- to late July) but the leaf growth is compressed into fewer weeks.
The planting process — step by step
- Source seed garlic from a UK supplier — the Isle of Wight Garlic Farm, Marshalls, Suttons, D.T. Brown, or a local nursery. Do not plant supermarket garlic — most is imported, treated with sprout inhibitors, and bred for warmer climates than yours.
- Break the bulbs into individual cloves the day of planting (any earlier and they dry out). Keep the papery wrapper on each clove.
- Sort cloves by size. Plant only the largest cloves — they produce the biggest bulbs. Cook the small inner ones.
- Prepare the bed with well-rotted compost worked into the top 20 cm. Garlic wants loose, free-draining soil. Heavy clay needs amending with grit or use raised beds — UK clay soils that sit wet all winter rot cloves.
- Plant cloves pointed-end up, 5 cm deep in mild areas, 8-10 cm deep in Scotland and the north. Space 10-15 cm apart in rows 25-30 cm apart.
- Water in if the soil is dry — though most autumn soil in the UK is already moist.
- Mulch with 5-8 cm of straw, leaf mould, or composted bark once the first hard frost is forecast. The mulch insulates against freeze-thaw cycles and suppresses weeds.
- Walk away until spring. Do not water through winter — UK rainfall handles it. Green shoots emerging before Christmas are fine; the foliage is fully hardy in the UK climate.
Harvest timing — next July
UK-grown garlic planted in October is harvested late June through July:
| Region | Harvest window |
|---|---|
| Channel Islands, Cornwall, south Devon | Mid- to late June |
| Southern England, Wales | Late June to mid-July |
| Midlands, northern England | Early to mid-July |
| Scotland, Northern Ireland | Mid- to late July |
The signal: harvest when the bottom 3-4 leaves have yellowed and dried but the top 5-6 leaves are still green. Each green leaf equals one wrapper layer on the bulb — if you wait until all leaves are brown, the wrappers split and the bulb will not store. If you harvest too early, the cloves have not filled out.
Hardneck growers get a mid-season bonus: scapes appear in early to mid-June (about 3-4 weeks before bulb harvest). Snap them off as soon as they curl once — this redirects energy to the bulb and gives you a delicious side ingredient for stir-fries and pesto.
Plot pairing — garlic with the rest of your veg
Garlic occupies the bed from October to July, which is convenient: the bed is empty over winter and clears just in time for a second crop of French beans, kale, or a summer lettuce sowing. Rotate garlic with the other alliums (leeks, onions, shallots) on a 3-year cycle to avoid soil-borne diseases like white rot (Sclerotium cepivorum) — a real UK risk on allotments with a long garlic history.
Garlic also makes a useful companion for tomatoes — the scent deters aphids and whitefly. Plant a row of softneck garlic along the front of your greenhouse beds and pull a few green ones in May for fresh "wet" garlic before the main harvest.
Related articles
- When to plant tomatoes in the UK — the spring counterpart to autumn garlic
- How to grow tomatoes — UK complete guide — what fills the bed after garlic harvest
- UK RHS hardiness ratings explained — find your area's rating and first-frost date for garlic timing
- How to grow basil — UK guide — pairs with garlic in the kitchen and the bed
Reviewed and updated by the Growli editorial team. For questions about anything here, open Growli and ask — or email hello@getgrowli.app.
Frequently asked questions
When should I plant garlic in the UK?
Plant garlic in mid-October across most of England and Wales for harvest the following late June to mid-July. Northern England and Scotland should plant in late September to early October to give the cloves enough warm soil time before the ground cools. The Channel Islands, Cornwall, and south Devon can plant from mid-October through early November in milder years. A second window opens in late February to early March for spring-planted varieties.
Is it too late to plant garlic in November in the UK?
Not in the south. Across southern England, Wales, and Cornwall, you can plant garlic through November if the ground is still workable and not waterlogged. The bulbs will be slightly smaller than mid-October plantings but still cropworthy. In the Midlands and northern England a November planting is risky — the ground often freezes before roots establish. Scotland: switch to spring planting instead.
What is the best garlic to grow in the UK?
For southern England: Solent Wight (softneck, RHS Award of Garden Merit, stores well into spring). For northern England and Scotland: Lautrec Wight (hardneck, the UK-bred classic, big easy-to-peel cloves). Both are bred specifically for UK conditions by the Isle of Wight Garlic Farm. For a single all-round variety, Solent Wight is the easiest place to start. Avoid imported supermarket garlic — most is treated and bred for warmer climates.
Can you plant garlic in spring in the UK?
Yes — plant cultivars sold for spring planting (Cristo AGM, Germidour AGM, Marco, or the dual-season Solent Wight) in late February to mid-March. Spring-planted garlic crops at about the same time as autumn-planted (mid- to late July) but produces bulbs 30-50% smaller. Use spring planting if you missed the autumn window, have heavy waterlogged clay, or live in the Scottish highlands where autumn plantings sometimes get killed by sustained sub-zero conditions.
How deep do you plant garlic in the UK?
Plant cloves pointed-end up, 5 cm deep in southern England, 8-10 cm deep in Scotland and the north. Space cloves 10-15 cm apart in rows 25-30 cm apart. Deep planting in the north protects against freeze-thaw heave that can push shallow-planted cloves out of the soil. In waterlogged clay, raise the bed rather than planting deeper — sitting in wet soil rots cloves.
Do you need to mulch UK garlic?
Yes — mulch with 5-8 cm of straw, leaf mould, or composted bark after the first hard frost is forecast. Mulch insulates against freeze-thaw cycles (the biggest UK winter risk), suppresses weeds in the early spring growth burst, and keeps moisture even through May and June. In Cornwall, the Channel Islands, and other mild micro-climates the mulch is optional but still helpful for weed control.
When do you harvest garlic in the UK?
Late June to mid-July across most of the UK, mid- to late July in Scotland and Northern Ireland. The signal: the bottom 3-4 leaves have yellowed and dried while the top 5-6 leaves stay green. Each green leaf equals one wrapper layer on the bulb. Dig with a fork rather than pulling (the stems can break off the bulb), then cure in a dry airy spot for 2-3 weeks before trimming and storing.
How does Growli know when to plant garlic in my UK postcode?
Add your postcode to Growli and the app ties the garlic planting reminder to your specific first-hard-frost forecast from Met Office data — counting back 4-6 weeks. The app also reminds you to source seed garlic in August, mulch after the first frost, snap scapes in June if you are growing hardneck, and harvest when the leaf signals appear the following July.