Introduction
Potatoes are one of the most rewarding crops to grow in the UK. However, knowing when to harvest potatoes in the UK can make the difference between small immature tubers and a full basket of perfect spuds. The exact harvest time depends mainly on the type of potato you planted and when they went into the ground.
In most UK gardens and allotments, potatoes fall into three groups: first early, second early, and maincrop varieties. First early potatoes are usually ready by early summer, while maincrop potatoes are lifted in early autumn for long‑term storage.
As a quick guide:
- First early potatoes are usually harvested June–July.
- Second early potatoes are ready July–August.
- Maincrop potatoes are typically harvested September–October.
However, weather conditions, soil temperature, and planting dates can all shift the harvest window slightly, so harvest dates should always be treated as a guide rather than an exact rule. The best way to judge readiness is by watching the plant itself, which we will cover below.
If you planted potatoes in spring, you will usually begin harvesting somewhere between early summer and mid‑autumn depending on the variety. For a full overview of seasonal crops, see the UK harvest calendar showing what to harvest each month, which covers vegetables, fruit, and herbs across the growing year.
Quick Potato Harvest Calendar (UK)
A simple table summarising when each potato type is usually ready.
| Potato Type | Typical Harvest Window (UK) | Time After Planting |
|---|---|---|
| First Early Potatoes | June – July | 10–12 weeks |
| Second Early Potatoes | July – August | 13–15 weeks |
| Maincrop Potatoes | September – October | 18–20 weeks |
This table gives a reliable overview for most UK gardens. However, the exact timing can vary slightly depending on your planting date, local climate, and the variety you are growing.
For example, potatoes planted in early March under fleece or in a greenhouse may be ready a couple of weeks earlier than those planted outdoors in colder soil. Likewise, cool northern regions or heavy clay soils can delay harvesting slightly.
Rather than relying on dates alone, experienced gardeners usually combine the calendar with visual signs from the plant, such as flowering, yellowing foliage, and skin development on the tubers.
Signs Potatoes Are Ready to Harvest
While harvest calendars are helpful, the most reliable way to know when to harvest potatoes is by looking at the plant itself. Potatoes send several clear signals as they reach maturity, and experienced gardeners often use these visual clues rather than relying on dates alone.
Flowering Plants
Many potato varieties produce flowers shortly before the tubers reach usable size. When you see flowers forming, the plant has usually started producing small new potatoes underground. At this stage you can gently dig around the plant and harvest a few tender new potatoes without lifting the entire crop.
It is worth noting that not all varieties flower, so this sign should be used alongside the others below.
Yellowing or Dying Foliage
As potato plants finish their growing cycle, the foliage will begin to yellow, wilt, and collapse. This is one of the clearest signals that the crop is approaching harvest time.
For maincrop potatoes, gardeners usually wait until the foliage has completely died back before lifting the crop. This allows the potato skins to toughen, which improves storage life.
Potato Skin Firmness
A simple test is to carefully dig up one potato and rub the skin with your thumb. If the skin rubs off easily, the potatoes are still immature and should be left in the ground for another week or two.
If the skin feels firm and does not rub away, the potatoes are mature enough to harvest and store.
Tubers Reaching the Right Size
Potatoes can actually be harvested at almost any stage of growth depending on the size you want. Many gardeners deliberately harvest early for small, tender new potatoes, which are perfect for boiling or salads.
However, if you are growing potatoes for winter storage, it is best to allow them to reach full size and wait until the plant naturally finishes its growing cycle before lifting the crop.
Harvesting New Potatoes vs Maincrop Potatoes
Not all potatoes are harvested at the same stage. In fact, the timing depends largely on whether you want tender new potatoes for eating straight away or fully mature potatoes suitable for storing through winter.
Understanding this difference helps gardeners decide when to start digging and how long to leave the crop in the ground.
New Potatoes
New potatoes are simply young potatoes harvested early, before the plant has finished growing. They are typically taken from first early or second early varieties and are prized for their thin skins and delicate flavour.
You can usually begin harvesting new potatoes 10–12 weeks after planting, often when the plants begin flowering. Rather than lifting the entire plant, gently dig around the base with your hands and remove a few tubers while leaving the rest to continue growing.
Because the skins are still soft, new potatoes do not store well and are best eaten within a few days of harvesting.
Maincrop Potatoes
Maincrop potatoes are grown for larger yields and long‑term storage. These varieties are usually planted in spring and harvested in early autumn, around 18–20 weeks after planting.
Unlike new potatoes, maincrop potatoes should be left in the ground until the foliage completely dies back. At this stage the tubers stop growing and their skins begin to toughen, which helps them store well through winter.
Many gardeners also cut the foliage off 1–2 weeks before lifting the crop. This allows the skins to fully set and reduces the risk of damage during harvesting.
How to Harvest Potatoes Without Damaging Them
Harvesting potatoes is simple, but taking a little care will prevent damaged tubers and improve storage life. The goal is to loosen the soil and lift the crop without slicing into the potatoes themselves.
- Choose a dry day if possibleDry soil makes harvesting much easier and helps prevent muddy potatoes. It also reduces the chance of rot developing during storage.
- Use a garden fork rather than a spadeA fork is less likely to cut through hidden potatoes. Insert it gently into the soil and lever upwards to loosen the ground.
- Start digging 25–30 cm away from the plantPotatoes often spread out from the base of the plant. Starting slightly further away reduces the chance of spearing tubers.
- Lift the plant and sift through the soilOnce the soil is loosened, lift the plant and collect the potatoes by hand. Smaller potatoes are often hidden in the surrounding soil, so take a moment to check the area carefully.
- Allow potatoes to dry briefly on the soil surfaceLeaving freshly dug potatoes on the soil for a short time helps the skins dry and toughen slightly. However, avoid leaving them in direct sunlight for long periods as this can cause greening.
With a little care, most of the crop can be harvested cleanly and undamaged, ready to eat fresh or prepare for storage.
What Month Are Potatoes Harvested in the UK?
In the UK, potatoes are typically harvested between June and October, depending on the variety and when they were planted. Early varieties mature quickly and provide the first fresh potatoes of the season, while maincrop potatoes are usually lifted in early autumn for storage.
Understanding the monthly harvest pattern can help you plan your growing season and make better use of your allotment space.
- June – First early potatoes begin
Gardeners who planted first early varieties in March often start lifting their first small new potatoes in June. These tender potatoes are perfect for boiling and eating fresh. - July – Peak new potato harvest
July is when most first early and second early potatoes are ready. Many gardeners harvest them gradually over several weeks rather than lifting the entire crop at once. - August – Second earlies finishing
By August, most second early potatoes are reaching full size. This is often the last chance to harvest tender new potatoes before the maincrop varieties begin maturing. - September – Maincrop harvest begins
Maincrop potatoes usually start finishing their growth in September. Once the foliage has died back, the plants can be lifted and prepared for storage. - October – Final lifting before frost
October is often the final potato harvest month in the UK. Gardeners typically lift the remaining maincrop potatoes before the first frosts arrive.
If you want a broader overview of what vegetables are ready throughout the year, see the UK Harvest Calendar – What to Harvest Each Month, which shows when different crops are typically harvested in British gardens.
What to Do After Harvesting Potatoes
Once potatoes are lifted from the soil, a little preparation will help keep them in good condition. Proper handling at this stage can make a big difference to how long your harvest lasts.
Allow Potatoes to Dry
Freshly dug potatoes often have moist soil clinging to them. Leave them on the soil surface for a short period or in a dry shed so the skins can dry and firm up slightly. This helps prevent rot during storage.
Avoid Washing Potatoes
It is best not to wash potatoes before storing them. Moisture can encourage mould and spoilage. Instead, gently brush off loose soil once the potatoes are dry.
Store in a Cool, Dark Place
Potatoes store best in cool, dark, and well‑ventilated conditions. Traditional storage options include paper sacks, hessian bags, or wooden boxes kept in a shed, garage, or cellar. Avoid light exposure, as this can cause potatoes to turn green and develop bitter compounds.
For long‑term storage, many gardeners leave harvested potatoes to cure for a week or two in a dry, frost‑free space before storing them properly.
If you want to learn more about preserving your harvest, see:
- How to Store Potatoes Properly
- UK Harvest Calendar – What to Harvest Each Month
- How to Grow Potatoes UK
Common Potato Harvest Questions
Can you harvest potatoes before they flower?
Yes. You can harvest potatoes before they flower if you want small, tender new potatoes. Flowering simply indicates that tubers are forming underground. Many gardeners begin carefully lifting a few potatoes around this stage while leaving the rest of the plant to continue growing.
How long can potatoes stay in the ground after they are ready?
Mature potatoes can usually remain in the ground for a few weeks after the foliage dies back, provided the soil is not overly wet and frost is not expected. However, leaving them too long increases the risk of rot, slug damage, or pest problems.
What happens if you leave potatoes in the ground too long?
If potatoes remain in the soil for too long, especially during wet autumn weather, they may begin to rot or suffer slug damage. The skins can also become rougher. For the best quality, it is usually better to lift the crop once the plants have fully died back.
Can potatoes survive frost in the ground?
Light frost on the foliage will usually kill the tops of the plant but does not immediately damage the potatoes underground. However, hard frost penetrating the soil can damage tubers, so it is best to harvest maincrop potatoes before prolonged freezing weather arrives.
Conclusion
In the UK, most potatoes are harvested between June and October, depending on the variety and when they were planted. First early potatoes provide the first fresh new potatoes of summer, while maincrop varieties are lifted in early autumn for winter storage.
Although harvest calendars are helpful, the best way to know when potatoes are ready is to watch the plant itself. Flowering, yellowing foliage, and firm potato skins are reliable signs that the crop is mature.
By combining the seasonal timeline with these simple visual checks, gardeners can harvest potatoes at the perfect stage — whether for tender new potatoes straight from the soil or a full crop ready for long‑term storage.
