One of the most low-maintenance crops, it’s well worth learning how to grow potatoes in bags.
Once you’ve discovered how much more flavoursome a simple home-grown spud can be compared to supermarket supplies, you won’t look back. Simple and easy to grow, potatoes are the perfect veg for a beginner to try as part of your garden ideas.
You can grow potatoes anywhere, and one of the best ways is growing potatoes in bags or containers. That means even if you have the tiniest outdoor space, you can add them to your plans for growing vegetables in pots as part of your courtyard garden ideas or balcony garden ideas.
How to grow potatoes in bags
‘Nothing beats the feeling of growing your own spuds. Potatoes are an excellent crop for both beginner gardeners and experienced vegetable growers, as they’re easy to grow and produce a bumper harvest every time. They can be grown outdoors in any setting in bags if you are short of space,’ explains Boyd Douglas-Davies, plant director at British Garden Centres (opens in new tab), the UK’s largest family-owned garden centre group.
You can carve out a little corner of your patio, courtyard or garden for your container-grown vegetables, such as if you’re also growing cucumbers, growing peppers or tomatoes in pots.
Boyd is the plants director at British Garden Centres, the UK’s largest family-run group. He has been in the garden industry for nearly 40 years.
Types of potatoes and when to plant them
A key part of learning how to grow potatoes in bags is knowing when to plant your tubers. For this, you need to understand the different potato types, as the time for planting – and for harvesting – can differ slightly for each variety.
‘There are four types of potatoes: first and second earlies, main crop, and autumn second crop, so called due to the time they are harvested,’ explains Boyd.
- First earlies – plant between February and April and harvest in May-July
- Second earlier – plant March to April and harvest July-August
- Main crop – plant March to May and harvest August-October
- Autumn (late season) – plant in August and harvest October-November
Ideally, plant at least three different types of seed potato, so you have potatoes throughout the summer season and even into autumn and winter.
Rob Smith, product development manager at vegetable seed suppliers, Suttons (opens in new tab), advises on varieties of the different potato types to try:
‘A good first early potato to grow is ‘Maris Bard’, which will provide large crops of new potatoes – delicious served warm with butter or cold in salads.
‘A classic second early potato with an RHS Award of Garden Merit is ‘Pink Fir Apple’. This variety produces knobbly, long pink tubers, which taste delicious in salads.
‘For an excellent all-rounder, try the main crop variety ‘Maris Piper’, whereas if you want a late harvest between October and Christmas then choose a late-season potato and plant at the end of August. Try ‘Charlotte’ for its good blight tolerance and excellent flavour,’ Rob explains.
Rob is development manager for Suttons, and a passionate vegetable gardener and writer.
What you will need
- Seed potatoes – ‘choose seed potatoes based on flavour, intended use and harvest time,’ says Rob.
- A good quality multi-purpose compost
- Seed trays or empty egg boxes
- Trowel or spade
- Potato planting bag, old compost sack, grow bag, large bucket or another type of container – about 40 litres in size, ideally
- Fork or potato harvesting scoop
- Paper bags or hessian sack
Growing potatoes in bags step-by-step
1. Select your grow bag or container
‘You can use any large, strong plastic bag as a potato container for growing potatoes in bags, for example, a rubble sack or compost bag. The most common size to use is 10 gallons to grow potatoes,’ says Boyd of British Garden Centres.
‘Make sure whichever bag you choose has strong side handles and ventilated holes on the bottom,’ he adds.
In fact, a pile of tyres, a large bucket or an old compost sack – with drainage holes – will do the job adequately. You simply need a sturdy container that’s at least 30cm deep and 30cm in diameter.
‘Once you have a grow bag, this can be placed in a bright place – perhaps on a patio or balcony, or even indoors. As long as the potato plants receive at least six hours of sunlight per day and frost isn’t likely to get to them, they will be as right as rain,’ explains Jeremy Oatey, Ginster’s farming partner at Hay Farm in Cornwall, and provider of the ‘Sow Your Own Slice (opens in new tab)‘ service, which gives people the opportunity to have potato and onion seeds sown on their behalf at the farm.
‘Key benefits of growing potatoes in bags are that your plants will be less susceptible to disease or pests, and can be moved out of bad weather if needed, allowing your plants to have the best chance possible of thriving,’ Jeremy adds.
Jeremy Oatey is Ginsters’ farming partner at Hay Farm in Cornwall. With many years’ experience of growing potatoes and other vegetables, he has a bounty of knowledge when it comes to growing food.
2. Chit the potatoes
Once you have chosen your variety of seed potatoes, they need to be ‘chitted’.
Each seed potato tuber you plant will send out lots of side shoots – chits – which all swell and become individual potatoes.
About four to six weeks before planting your seed potatoes, ‘arrange a single layer of seed potatoes in trays or empty egg boxes, with the rose ends – those with the most ‘eyes’ – pointing upwards. Place them in a cool, but sunny spot where there’s no risk of frost. Short, dark green ‘chits’ will form in a few weeks,’ explains Rob Smith.
The potato tubers are ready to plant when the sprouts are approximately 2.5cm long.
3. Plant the potatoes
‘Find a sunny and frost-free spot for your planters or bags and fill the bottom third with multipurpose compost,’ says Rob Smith.
You could even learn how to make compost so you can use this for growing potatoes in bags.
‘Add your chitted potatoes with the sprouts pointing upwards, making sure they have a bit of space around them – about 15cm – and cover with another 10cm layer of compost and water well,’ says Jeremy Oatey.
Don’t fill up the pot with compost, but ‘make sure that none of the potatoes is exposed to sunlight,’ adds Boyd Douglas-Davies
4. Top up the container
‘Once shoots have sprouted around 10cm through the soil, add another 10cm of soil or compost – with the sprouts still above the surface – and water again. Keep doing this every few weeks, while rolling up the sides of the potato growing bag and watering every three days or so,’ explains Jeremy.
‘This is known as “earthing up”,’ adds Boyd. ‘Repeat this until the soil is 5cm from the top of your bag. This will reduce the risk of light exposure, which turns potatoes green,’ he adds.
5. Water and fertilise the potato plants
Once planted, looking after your potato plant is very easy. ‘Simply water regularly, making sure that the soil is always slightly moist and never dries out. If your plants start wilting, they need more water,’ says Jeremy.
‘In dry weather, water plants in the early morning or late evening. After about a month, start adding liquid tomato feed when watering,’ adds Rob Smith.
6. Harvest the potatoes
When flowers start to appear on the potato plants, or the leaves of your plants begin to turn yellow and die back, your homegrown potatoes are ready to harvest.
‘To be certain, gently dig in the compost with your hand and check the size of the potatoes. Although the foliage will turn yellow and die off when your crop is ready, your potatoes can remain in the compost for 2-3 weeks, so you can simply dig them up as you need them,’ says Rob Smith.
Remember: any green potatoes are inedible and you should discard them!
‘If you want to harvest them all at once, then tip your container out onto a tarpaulin to remove all the potatoes and allow them to dry out in a well-ventilated spot for a few hours to cure the skin.
7. Store potatoes correctly
‘Once your harvest potatoes are dry, store them in paper potato sacks and place them somewhere dark, cool, and frost-free. Avoid storing potatoes in polythene bags because this can cause them to rot,’ says Rob Smith.
Then all there is to do is prepare and cook these eminently versatile, and delicious homegrown spuds.
Growing potatoes in a bag FAQ
How long do potatoes take to grow in a grow bag?
How long potatoes take to grow in bags depends on the variety you choose to grow.
‘Choosing which variety of potato to grow at home largely depends on when you’re looking to harvest and also what type you would like to eat. If you’re looking to plant and wait as little time as possible, choose Arran Pilot or Rocket potatoes. Both are harvestable after just 10 weeks and are delicious in a summer salad,’ says Jeremy Oatey.
‘Those patient enough to wait an extra 3 weeks could plant a Charlotte potato or perhaps a British Queen potato. For those looking to get ahead on autumn dinners and don’t mind waiting the full 20 weeks, they can try Maris Piper or King Edwards – both are easy to grow, will be fuller in size and would make great chips or mash,’ Jeremy adds.
How many potatoes do you plant in a bag?
How many potatoes to plant when growing potatoes in a bag will depend upon the size of the bag used. The key thing is to leave enough space between each potato for them to grow.
You should plant about three or four seed potatoes, and space them about 15 cm apart. If you are using a smaller bag then plant fewer seed potatoes.
‘Carefully place three or four seed potatoes onto the compost with their shoots pointing upwards. Space them equally apart, not too close to the edge of the container,’ says Rob Smith of Suttons.