Many of us don’t have the space for a vegetable plot in the back garden but still want the taste and satisfaction of homegrown vegetables. Luckily the humble potato will grow just about anywhere if you follow a few basic rules. And a major advantage of using containers for potatoes is portability – put them in a lovely sun trap for great crops fast.
You can buy potato barrels and potato bags but you can grow potatoes in just about anything. You could use a compost bag, gardening tub or even a stack of old car tyres. For a larger crop, use an old dustbin or for individual plants, a pot will do. On average, you’ll get 5-10 potatoes from one plant. The two basic rules of your container potatoes are space for the crop to grow and a few holes punched into the bottom of the container to let water drain out. Potatoes are thirsty but will rot if they sit in water. Buy a good multi-purpose compost and take the time to break it up and remove any large woody bits. Mix in slow release potato fertiliser or fish, blood & bone fertiliser and lay about 15 to 20cm (4-6”) at the base of the container – if it’s a bag, fold down the edges for access.
Buy seed potatoes from a garden shop. The best spuds for container growth are first and second earlies, as they are known. Try Elisabeth and Annabelle (ideal all-rounders), Lady Christl and Vales Emerald (new potatoes), Red Duke of York (heritage), Winston (baking), Rocket and Maris Bard (high yield) or Anya and Charlotte (salad). It’s a good idea to chit them before planting.
Chitting is basically another word for sprouting, where you speed up the ageing process of the potato by exposing it to light and warmth before planting. Put your seed potatoes somewhere warm (8-10°C) and light – a greenhouse or porch ideally. The eyes of the potato will sprout and the sprouts should be small, knobbly and green/purple in colour. If you end up with long, white spaghetti-like sprouts, it means they don’t have enough light, or you’re sprouting shop bought potatoes. Put the seed spuds in a single layer with the majority of eyes facing upwards. Recycle old egg boxes if you’re only chitting a few, or use lightly screwed up newspaper on trays for more – the potatoes just need to stay upright. You want two or three good size chits on your potato for planting – if there are more, rub the extras off and you’ll get a better harvest. Start chitting towards late February, as it’ll take 4-6 weeks before they’ll be ready for planting.
You want to plant about two weeks before your last frost date, which is March or April for most of the UK – these dates are based on historical averages and depend on where you live but potatoes will survive a frost or two. Place your chitted seed potatoes, sprouts up, on top of the compost. As a rule of thumb use one potato for a 25cm (10”) wide container, three in a 40cm (18”) container and five for a dustbin. Then cover the spuds with another 15 to 20cm of your compost mix. Water regularly, preferably from a water butt rather than the tap. If you haven’t got a butt, let the tap water sit in the watering can for 12-24 hours before using it.
After a couple of weeks, depending on temperature and sunshine, you should see potato plants starting to sprout through the compost. As they grow, keep covering the plants in more compost, until you reach about 2 inches below the top of your container. This protects your potatoes and the plants from light and frost. You don’t want soaking compost, but it needs to be moist for the potatoes to grow; you will need to water morning and evening in the height of summer. Once the plants are growing free, water straight into the soil – you don’t want it running off the foliage and not getting to the roots.
Once the plants have fully flowered the potatoes are ready for harvesting. If you’re growing in small containers, simply take the top off the plant, remove some compost and take your delicious homegrown spuds out. Store them in a single layer in a cool dry and dark place – potatoes go green in the light. If the container has more than one plant, or you only want a few potatoes at a time, gently burrow your hand in the soil until you find potatoes of the correct size and pull them out carefully. Try not to disturb the soil and roots too much and pat the compost down again down again afterwards. The plant will happily continue to grow potatoes.
The compost in the container can be reused for other potted plants and veggies while you enjoy your homegrown potatoes!