Seed potatoes are now on sale!

We now have a number of different varieties of seed potatoes on sale – both in bags and selected varieties loose so you can pick and grow your own potatoes!
If you’ve never grown your own before, why not use our guide below to give it a go? You don’t need much space – you can even grow your own potatoes in large containers or potato planters…

What variety of seed potato to choose:

Potatoes are grown from special ‘seed’ potatoes (also called tubers), which are very like the potatoes we buy to eat, but they’re certified virus-free.
There are many different potato varieties, usually described as early, second early and maincrop potatoes.These names indicate when they crop and also give you an idea of the space you’ll need, how closely and when they can be planted.
You should concentrate on the earlier types if you’re short of space, and it’s also worth remembering that earlies are less likely to encounter pest problems as they’re lifted so much earlier in the year.
Second earlies take 16 to 17 weeks to mature after planting, so you should be able to harvest them from  June through to the start of August.
Maincrops are ready 18 to 20 weeks after planting, so they can be lifted usually from July through to October. Maincrops take up the most space in the garden, but they tend to be the best varieties to grow if you want some for storage.

Once you’ve chosen your variety you need to CHIT them:

seed potatoes that have been chitted ready for planting

Chitting simply means encouraging the seed potatoes to sprout before planting.
Start chitting from mid-late January in Guernsey, about six weeks before you intend to plant out the potatoes.
Each seed potato has a more rounded, blunt end that has a number of ‘eyes’.
Stand the tubers with the blunt end uppermost in trays or old egg boxes, with plenty of natural light in a frost-free place.
The potatoes are ready to be planted out when the shoots are 1.5-2.5cm (0.5-1in) long. On early potatoes, rub off the weakest shoots, leaving four per tuber.

How to plant:

Here’s a link to a RHS video showing how to plant your chitted seed potatoes

Plant your chitted potatoes when the soil has started to warm up, usually from March or early April. If you’re planting in containers you can start even earlier.
Potatoes need a sunny site away from any areas susceptible to frost pockets (fortunately we’re unlikely to have problems with frosts in Guernsey). Start by digging a trench 7.5-13cm (3-5in) deep, although the exact depth should vary according to the variety of potato you’re planting.
Add a light sprinkling of fertiliser to your trench before you begin planting.
Plant early potatoes about 30cm (12in) apart with 40-50cm (16-20in) between the rows, and second earlies and maincrops about 38cm (15in) apart with 75cm (30in) between the rows.
Handle your chitted tubers with care, gently setting them into the trench with the shoots pointing upwards, being careful not to break the shoots. Cover the potatoes lightly with soil.
As soon as the shoots appear, earth up each plant by covering it with a ridge of soil so that the shoots are just buried.
You need to do this at regular intervals and by the end of the season each plant will have a small mound around it about 15cm (6in) high.

Growing in containers

Small crops of potatoes can also be grown in large, deep containers, and this is a good way of getting an early batch of new potatoes. Fill the bottom 15cm (6in) of the container with potting compost and plant the seed potato just below this. As the new stems start growing, keep adding compost until the container is full.
 

Harvesting

Your home-grown potatoes should be ready for lifting from June until September, depending on the varieties and the growing conditions. Earlies can be lifted and eaten as soon as they’re ready.
This will be when above-ground growth is still green, and usually as soon as the flowers open.
Second and maincrop varieties can be kept in the ground much longer, until September, even though above-ground growth may well be looking past its best.
Two weeks before you lift the crop, cut the growth off at ground level. This should give the skins of the potatoes sufficient time to toughen up, making them far less prone to damage from lifting and easier to store.
 
Credit: www.rhs.org.uk and www.bbc.co.uk/gardening