Once you've learned how to grow potatoes, you'll wonder why you ever bought them from the supermarket in the first place. Homegrown potatoes are packed full of flavour and are perfect for all your favourite dishes, from creamy mash to crispy roasts.
You might be tempted to plant potatoes that you have sitting leftover in your cupboards, and you can do this, but your crop won't be as reliable as if you use seed potatoes. These are small potato tubers, rather than actual seeds, that are virus-free and bred to produce bumper crops. You can buy seed potatoes from most garden centres from late winter.
Before planting, you'll need to ‘chit’ your potatoes, which means letting the seed potatoes grow shoots so you get a bigger crop. Simply place the seed potatoes in trays of egg boxes with the part that has the most eyes uppermost. Stand in a cool, light spot until 1-2cm shoots form, which usually takes about six weeks.
When you come to move your potatoes outdoors, choose a sunny position with fertile, well-drained soil. You can grow most potato varieties in beds, but if you're short on space, choose early or salad varieties to grow in containers or potato bags.
What kind of potatoes can I grow?
There are lots of types and varieties of potatoes, but these can all be be classed as either early, second early or maincrop potatoes. The type of potato dictates when they're planted and therefore when they're ready to harvest.
First earlies are usually planted in late March and are ready to harvest in June or July. These are the best choice if you have limited space and well grow well in bags and containers. Try 'Annabelle'.
Second earlies, which include salad varieties, are planted in early to mid-April and are harvested from late June to August. Try 'Charlotte' or 'Cherie'.
Maincrop potatoes are planted from mid to late April and are harvesting from the end of August to October. These potatoes take up the most space to grow but are the easiest to store. Try 'Cara' or 'Setana'.
How to grow potatoes
1. Once your potatoes have been 'chit', prepare the ground by turning plenty of compost through the soil.
2. Plant with the shoots facing upwards. Plant first and second earlies about 12cm deep and 30cm apart, and leave 60cm between rows. Maincrop potatoes need to be about 40cm apart with 75cm between rows.
3. Water regularly and make sure you keep the soil weed feed.
4. As the plants grow, use a spade or hoe to cover the shoots with soil and stop the potatoes becoming green, which means you can't eat them. This process is called 'earthing up' and you just need to leave a few centimetres poking out the top of the soil. Do this regularly as the plants grow.
5. Potatoes will need a liquid fertiliser every other week, unless you mix granular fertiliser in with the compost before you plant.
6. Potatoes are ready to harvest about 10 weeks after planting, when the potato plants are flowering. Second croppers are ready by about mid-November, but you'll need to protect them from frost by either moving the bag or container into a greenhouse, or covering the top with straw.
How long do potatoes take to grow?
Depending on the type of potato you are growing, you’ll have crops from May to October.
You should harvest first and second earlies when the plants are still flowering and the potatoes are about the size of a big hen’s egg. Maincrop potatoes are ready when the leaves turn yellow and die down.
Weather conditions permitting, first early potatoes should be ready to lift in June and July; second earlies in July and August. Maincrops should be ready to harvest from late August through to October.
How to store homegrown potatoes
The best type of potatoes for storing are maincrops as they have thicker skins to protect them. Stored in a cool place in paper bags they can last for many months. Only store perfect potatoes and throw out any that are green, as they are poisonous. If you have too many, blanch and freeze ready to make into chips or roasts. Mashed and dauphinoise potatoes can also be frozen.
Common problems with growing potatoes
The biggest issues when growing potatoes are slugs and potato blight. Discourage slugs by adding grit to your mulch, planting lavender or rosemary nearby, or, if all else fails, using slug pellets.
To avoid potato blight, which is a fungal disease that turns leaves yellow and causes the potatoes to rot, grow blight-resistant varieties. As soon as you spot infection in the leaves, cut the plants down as the blight won't yet have reached the tubers.
Grow potatoes in new soil each year to prevent build up of pests and diseases.