Potatoes: Top Tips

“If you’ve never tasted a first early potato straight out the ground then you don’t know what a potato tastes like.” John Barber, allotment holder in East London

Should I grow them?
Potatoes need a lot of space. Spuds are also dirt cheap in the shops, especially the larger ‘maincrop’ potatoes which last through winter. So don’t bother growing potatoes if you have a tiny vegetable patch.

The key is to only grow unusual, early varieties not available on the high street. They comes in many colours, shapes and sizes. And try a few in containers – potatoes grow easily this way. Note that it’s essential to buy certified seed potatoes, about 10p each, for planting as they are guaranteed to be disease free. Don't be tempted to use potatoes from the supermarket.

What are the key points?
The language around potatoes can be confusing. Here’s a jargon buster:

Early potatoes: These varieties take the shortest time to be ready to eat. There are first earlies (plant in March, ready June) and second earlies (plant in April, ready July / August). They take around 12 to 13 weeks from planting to lifting out of the soil, and are eaten straight away.

Main crop: These are the larger potatoes which take longer to grow and you can store through winter. Plant around May, dig up around September.

Haulm: The stem and leaves of the plant.

Chitting: This is the technique of letting the potatoes develop green shoots before planting. Put them in cool place, out of direct sunlight, with ‘rose end’ up (this is the end of the tuber with most eyes). When two or three shoots develop, an inch or so long, they are ready for planting.  This will take around a month. You don't need to chit maincrop potatoes.

[Pic: a chitted potato]

Earthing up: This is the technique you use as the plant grows. You scoop up soil around the growing plant (the ‘haulm’) when it is about nine inches high. This encourages more tubers to grow, cutting out the light and stopping them from turning green. It also protects the haulm from frost. 

Blight: A fungus which is devastating to potatoes. It is often worse in wet summers.

Scab: Another disease, with no real remedy. But you can still eat the potatoes.

How do I grow them in containers?
You do need a large container. Some people favour dustbins. An easy method is to buy special potato growing bags. They are black polythene bags, with a 30 litre capacity. Whatever you choose it needs to be at least 30cm deep and wide. Use multi-purpose compost, preferably loam-based, as this is more moisture retentive. Keep it moist, not wringing wet, at all times.  Plant a couple of potatoes in smaller pots, up to six in dustbin-sized containers. Earth up as the plant grows. When the leaves come over the top of the container, give it a twice weekly feed with a bit of tomato food, comfrey juice or seaweed extract.

What about in the soil?
Earlies need 15 inches between plants, in rows about 20 inches apart. Maincrop potatoes need a few inches more in either direction. Potatoes like a rich soil which is slightly acid. Some growers line their potato trenches with comfrey leaves to help them on their way.

Which varieties should I choose?
There is an immense range. First earlies: Belle de Fontenay; International Kidney. Second earlies: Charlotte. Red Duke of York can be used as a first early, second early and main crop.

Guardian article.
Independent article.