Potatoes are a national staple for gardeners and cooks, and it’s no wonder! They are endlessly versatile crops for cooking and quite easy to grow too. They need a fair amount of space and nutrients, but with the option to grow in containers or bags you don’t need a whole garden to grow your own potatoes. One single potato plant can yield up to 10 potatoes, so just a few plants can go a long way.
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Potatoes are cool weather crops, which means they like to do the majority of their growth outside of the high heat of summer. Potatoes, therefore, are most commonly planted in the early spring, a few weeks before the frosts have passed. If you’re hoping for Christmas dinner roasties, then you can try planting as the summer is coming to an end so they are ready to harvest in December but choose your varieties carefully.
First Early, Second Early & Maincrop Potatoes
There are three main types of potato, separated by their planting/harvesting times.
As the label suggests, first early potatoes are those varieties which can be planted and harvested first (plant out from end of February and harvest from June). These are ‘new’ potatoes, harvested while the tubers are still small. They take 10-12 weeks to mature. Because of their fast growing cycle and small tubers, they are good for growing in containers and bags.
- Plant Out: From end of February
- Harvest: From June (10-12 weeks after planting)
- Location: direct, bags, containers, raised beds
- Spacing: in rows 30cm apart, 60cm between rows
First Early Potato Varieties:
‘Red Duke of York’, ‘Lady Christl’, ‘Orla’, ‘Rocket’, ‘Arran Pilot’, ‘Casablanca’, ‘Home Guard’, ‘Maris Bard’, ‘Pentland Javelin’, ‘Abbot’, ‘Epicure’, ‘Purple Majesty’, ‘Swift’.
Like first earlies, second early potatoes are eaten as ‘new’ or salad potatoes and don’t store very well, but take a few more weeks to mature than the first early varieties - about 14-16 weeks. These are also a good choice for growing in containers and growing bags.
- Plant Out: From mid March
- Harvest: From July (14-16 weeks after planting)
- Location: direct, bags, containers, raised beds
- Spacing: in rows 35cm apart, 75cm between rows
Some second early potatoes can be grown for ‘Second Cropping’, which means they can be planted in August for harvesting at Christmas time. These will need frost protection and are best grown in bags in a greenhouse. There is no need to chit these potatoes, as the ground is already warm enough to speed them along their way. Once the tubers reach their desired size, cut back the stems, mound up earth to cover them (straw or sacking can be used for further insulation too) and harvest them as needed.
- Plant Out: Early August
- Harvest: From November (10-11 weeks after planting)
- Location: covered raised beds or bags inside greenhouse
- Spacing: in rows 30cm apart, 60cm between rows
Second Early Potato Varieties:
‘Charlotte’, ‘Maris Peer’, ‘Anya’, ‘British Queen’, ‘Elfe’, ‘Jazzy’, ‘Kestrel’, ‘Vivaldi’, ‘Apache’, ‘Athlete’, ‘Jester’, ‘Ratte’.
Maincrop potatoes are those like your common baked potato and mash spuds. They store well and you can eat them months after harvest. The plants and their tubers are much larger than first and second early potatoes and as such take longer to mature at about 15-20 weeks.
- Plant Out: From March to mid May
- Harvest: From late August (15-20 weeks after planting)
- Location: direct, raised beds
- Spacing: in rows 45cm apart, 75cm between rows
Maincrop Potato Varieties:
‘Adessa’, ‘Maris Piper’, ‘King Edward’, ‘Desiree’, ‘Cara’, ‘Golden Wonder’, ‘Picasso’, McCain ‘Royal’, ‘Pink Fir Apple’, ‘Rooster’, ‘Salad Blue’, ‘Sarpo Mira’, ‘Setanta’, ‘Vales Sovereign’, ‘Valor’, ‘Mozart’.
NB: Sweet Potatoes - sweet potatoes are a slightly different beast to British spuds, being used to warmer climates than we have in the UK. They can be grown here, but require a little more attention, so the advice given in this article may not always apply.
The Best Cooking Varieties:
- For jacket potatoes or baked potatoes: ‘Maris Piper’, ‘Maxine’, ‘Maris Peer’, ‘Nadine’, ‘King Edward’
- For roast potatoes: ‘King Edward’, ‘Kerr’s Pink’, ‘Arran Victory’, ‘Sarpo Axona’
- For mash potato: ‘Kestrel’, ‘Wilja’, ‘Vivaldi’, ‘Arran Victory’, ‘King Edward’, ‘Maris Piper’
- For Christmas harvesting: (look for Second Cropping varieties) ‘Nicola’, ‘Charlotte’, ‘Maris Peer’
- For salad potatoes or new potatoes: see First Early and Second Early Varieties. [anchor links]
- Sweet Potatoes: ‘Erato Orange’, ‘Makatea’, ‘Tahiti’, ‘Erato White’, ‘Tatakoto’
Chitting Potatoes: Buy Seed Potatoes or Produce Your Own at Home?
It is easy to grow your own potatoes with ‘seed potatoes’. Seed potatoes are not seeds but tubers, like any other potato. While potatoes can produce seeds, they are rarely used by growers because of poor viability. Seed potatoes can be identified by their shrivelled appearance and sprouting roots (or eyes). You may have seen this happen to your uneaten potatoes in the cupboard or pantry.
It is possible to plant potatoes from those left in our cupboards rather than purchasing seed potatoes. However, be warned that they won’t always produce viable plants and non-organic potatoes bought in shops may have been treated with chemicals to increase shelf-life (and inhibit sprouting) which might also damage your soil and lead to other plant diseases. Seed potatoes, on the other hand, are grown for the purpose of replanting and are cultivated for good yields and healthy plants – seed potatoes are certified virus-free.
The other benefit of buying seed potatoes is that they are ready to plant a few weeks after you buy them (once you have chitted them), whereas nurturing your own will take months of forethought.
How to Chit Potatoes
What is chitting? It is the practice of letting tubers sprout prior to planting. Well chitted potatoes will lead to stronger plants once in the ground. It also allows you to identify any potatoes that fail to develop so they can be discarded before planting.
Regardless of buying seed potatoes or choosing from your own stock, chitting is strongly encouraged. Around 6 weeks before planting out, place your seed potatoes on a bright windowsill or in the greenhouse with the eyes pointing up. You’re hoping for 1-4 sprouts per potato (remove any extra), each around 2.5-3cm long. They should be green or purple in colour; white sprouts are a symptom of light insufficiency.
Planting & Nurturing Potato Plants
Quick tips for planting and caring for potatoes:
- Avoid planting in the same place as last year to avoid any disease left in the ground.
- Plant in slightly acidic, well-draining soil.
- Plant in a location with full sun.
- Loosen the soil before planting to a depth of around 1 ft.
- Mix well rotted organic matter (e.g. compost or well rotted manure) into the soil before planting.
- Plant with eyes facing up.
- Can be grown in a variety of locations: direct, raised beds, bags and containers. Consider which location will work best for the variety and for the space you have.
- Remove poisonous tomato-like berries from the plant if they appear.
- Keep tubers covered and mound up as the plant grows. (Potatoes become poisonous when exposed to the sun and turn green.)
Create a good ground environment
It is best to prepare your planting area well in advance of planting your potatoes - preferably in November or December, so the soil has a chance to settle. Turn over the soil to loosen it, removing any weeds or large stones, and while you’re at it, incorporate plenty of well-rotted organic matter.
Potato plants, like all root vegetables, need to gather a lot of energy and store it to grow large and tasty tubers. Potatoes take a lot of nutrients from the soil – nitrogen, potassium, phosphorus. Potatoes prefer a slightly acidic environment but can tolerate most soil types. These hungry plants will exhaust your soil, so don’t plant potatoes in the same place next year! Rotate your crops to ensure the area gets reinvigorated.
Potatoes like to be watered regularly
Particularly once they start flowering because this is when tubers are growing below ground. Consistent watering is good, but over-watering will lead to rotten tubers, so keep a close eye on them to make sure they aren’t soaked all the time. Free draining soil is ideal.
Mound up earth around growing tubers
Once they are 20cm tall, mound earth up around the plants to halfway up the stem – this is called “earthing up”. Do this throughout the growing period. By drawing up the soil around the stems, you are encouraging growth. You also want to ensure the growing tubers remain covered with plenty of soil to prevent them from going green in direct sunlight as they start to photosynthesise. If growing in a bag or container, when planting, only partially fill the container, leaving space to add earth and mound up as it grows.
Remove poisonous berries
The fruits and seeds that grow above ground on potatoes are poisonous so this is of particular concern to dog owners or those with young children in the garden. Removing fruits also prevents the plant from going to seed too soon.
NB: Poisonous Potatoes - some parts of potato plants are poisonous - green potatoes, fruits and seeds. It is absolutely essential that you mound up the potatoes while in the ground and store them in a dark dry place once harvested to prevent green potatoes.
Salad or baby new potatoes should be harvested while the plant is still flowering. Cut down the stems to the ground, then gently unearth the potatoes as and when they are needed. The remaining potatoes can be left in the ground until you wish to use them, just make sure they are covered in earth to prevent them from going green.
Maincrop potatoes should be left until the leaves on the plant start to die back. Then, as with the new potatoes, cut the plant down to the ground and unearth the potatoes carefully. Discard any that have started to rot or show signs of damage. Leave any you don’t wish to consume immediately in the earth, ensuring they are well covered.
Some varieties of potato make for better storage potatoes because they have a long dormancy period (i.e. they are slow to sprout). Some varieties that are good for storage are: ‘Pink Fir Apple’, ‘Kerr’s Pink’, ‘Majestic’, ‘Maris Piper’, ‘Jazzy’ and ‘Sarpo Axona’.
Potatoes can be stored for several months before being eaten. Just make sure you follow these steps:
- Keep them in darkness (or they will turn green)
- Remove any that show signs of damage or rot that may spread to the rest
- Don’t wash them (just brush off excess soil; residual moisture will cause problems)
- Keep them in a dry, cool, frost-free place with good ventilation
Common problems with growing potatoes
Potato Blight – a fungal disease which turns leaves yellow/brown and can result in rotting tubers. Often occurs in excessive humidity – too wet and too warm. There is no complete remedy for potato blight. Cut away affected leaves where possible, but cutting back too much will prevent good tuber growth. You may decide it is better to dig it up, harvest what you can and discard the rest – do not compost.
Green Potatoes - potatoes turn green when exposed to sunlight. These are poisonous if ingested. This is easily avoided by keeping covered by mounding up while in the earth and storing in darkness once harvested.
Common Scab - a soil-borne disease that is often left undetected until harvest times arrives. It presents as dark murky lesions on the skin of the potatoes. Affected areas can be cut away so the potatoes remain edible, but more seriously affected plants can lead to bigger problems. The bacteria that cause scabby potatoes can remain in the soil for a long time, living off decaying plant matter, so remove as much as you can once harvested. Crop rotation will aid prevention in future crops.
Potato Rot - a common problem with homegrown potatoes that can occur during and after lifting due to wet conditions. Avoid over-watering during maturation and ensure potatoes are dry before storage.
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