Potato crop sheet

Information sheet

Potatoes are incredibly versatile, being cooked in countless ways to make a meal and they are easy to grow! Potatoes are grouped according to their season; first earlies, second earlies and maincrop.

  • School term: All year round
  • Level of experience: No experience needed
  • Subject(s): Science

Sowing

When: March to May

Planting times for potatoes depend on what type of potato you choose to grow;

  • First Earlies - start chitting in February and plant out late March to early April
  • Second Earlies - chit these in March and plant out early to late April
  • Maincrop - chit these in late March to early April and plant out in late April to mid-May

Chitting or to chit your potatoes is when you allow them to grow shoots (small new growth or leaves) before planting. 
To chit your potatoes the best method is to stand them up, with the end that has the most dents or eyes facing upwards. You can do this by standing them in an old egg box or tray, in a light and frost-free location. Let the shoots grow and once they are 3cm long your potatoes are ready to plant. 

Planting in pots - see 'How to grow potatoes in containers' 

  1. Potatoes are ideal to grow in large tubs, containers or pots. Make sure they have drainage holes in them to allow excess water to escape. This will stop your potatoes rotting, as they don't like it too wet.
  2. Firstly place compost in your tub, container or pot. Only fill up to one quarter of the container or 15cm with compost. 
  3. Place the chitted potatoes spaced out, on the surface of the compost. Make sure the shoots are pointing upwards and then cover them with compost. If you are growing in a grow bag, space the potatoes far apart.
  4. Now water your potatoes. Potatoes need watering every 10-14 days and more during dry periods. 

Planting in the ground

  1. Firstly you will need to prepare the space or bed where you are planting your potatoes by removing any weeds and large stones. If you are adding well-rotted manure or garden compost to boost the nutrients in the soil, make sure this is done at least 6-8 weeks before planting or in the previous autumn or late winter. 
  2. Once you have prepared your soil and are ready to plant, dig a narrow trench. This will make it easier to earth up your potatoes as they grow. Place the soil you have dug up along the side of the trench. 
  3. In the bottom of the trench, make holes along a measuring stick about 8-15cm deep and 30-37cm apart in the row. The planting depth and spacing will depend what potato variety you have so check your packaging. You can use a trowel or bulb planter to do this.
  4. Plant the potatoes at the bottom of the holes with the shoots pointing upwards, cover with soil.
  5. If planting in a vegetable bed, the next row of potatoes should be 60-75cm apart to allow for earthing up.  
  6. Then water in your potatoes. Remember potatoes are a thirsty plant, so keep watering them especially in hot weather. If the soil remains damp and wet rather than drying out, make sure you don't over water your potatoes as they could rot. 

Growing

  • ‘Earthing up’ is a term where the soil is heaped up over the emerging potato plants green shoots. Keep covering your potatoes with soil or compost as the green shoots grow, making sure you cover the shoots and leaves each time. A hoe is the best tool for this job if you are planting in beds.
  • Water your potatoes after earthing them up to encourage them to grow more. Remember to keep watering your potatoes if you live in a dry area or if they are growing in large tubs, containers or pots, as these can dry out quickly. 
  • Potatoes will produce flowers and green tomato like fruit before they are ready to harvest. Be aware that these fruits and flowers are poisonous and not edible, so please do not eat them.
  • See the top tips section for information on pests and diseases of potatoes. 

Harvesting

When: June to October. Potatoes take a set number of days to mature; First Earlies take 100-110 days, Second Earlies take 110-120 days, and Maincrop take 125-140 days.

  • With First and Second Early potatoes harvest them once they flower or just after the flower buds drop off. Your potatoes should be about the size of an egg and are ready to harvest. 
  • For Maincrop potatoes wait until the foliage begins to dies back before harvesting. Wait for the foliage to turn yellow then cut it back and compost it. After doing this wait 10 days and this is when the potatoes or tubers are ready to lift.
  • Lift potatoes very carefully, as using a garden fork can damage them. If your potatoes are in a tub, container or pot you can lift them by digging them out with your hands. A fun way to get your hands dirty!
  • Once harvested, brush off any excess soil and leave them in a warm, dry place to dry off for a few hours. This will help them last longer in storage. 
  • Store your potatoes in a dark, dry location. Putting them in a hessian sack is ideal. Don't put or leave them in plastic wrapping as this can become humid and form condensation, which can cause rotting and sprouting. 

Using

  • Potatoes are a staple in the UK diet as they grow well here, so there are tonnes of options for what you can make with your home grown potatoes. You could go with a classic meal option and boil, mash or roast them.
  • If you want to do something different with your home grown potatoes, try these; potato tray bake, soup, stew, Bombay potatoes, Saag aloo, potato wedges, potato pie, potato salad, Hassel back potatoes, frittata, jacket potatoes, Shepard's pie, gratin, curry, Dauphinoise potatoes, Duchess potatoes, potato nachos, Hash browns, chips or fries. 
  • Are you wanting to grow you potatoes to share as part of the Big Soup Share? Then why not try one of these delicious soups; Kindergardencook's Perfect Potato and Leek Soup, Comforting Courgette and Root Vegetable Soup or Sharon's Creamy Corn Chowder.  

Varieties to use

  • 'Red Duke of York' (First Earlies) - a heritage variety of potato that has lovely deep red skin and yellow, floury flesh. Has a wonderful strong flavour and can be roasted, mashed, baked or turned into chips.  
  • 'Charlotte' (Second Earlies) - a popular salad variety which has a lovely smooth yellow waxy skin and creamy-yellow flesh. Tasty hot or cold!  It is resistant to scab and blight, so is an easy and reliable potato to grow. 
  • 'Maris Piper' (Maincrop) - a very well loved potato variety with creamy-white flesh, which can be found in every supermarket. These potatoes are incredibly versatlie and can be used for roasting, baking, mashing, boiling or turning into chips or wedges. Yum!
  • 'Pink Fir Apple' (Maincrop) - an exciting knobbly variety with a unique earthy flavour. It has lovely pink skin with butter yellow, waxy flesh. It is a fantastic salad potato enjoyed hot or cold but also tastes amazing as skin-on chips. 

Potato Blight

  • In warm and wet summers potato blight is very damaging for potatoes. It appears as a watery rot on leaves that soon causes them to shrivel and turn brown. Blight can also cause brown lesions to appear on stems and a reddish brown decay under the skin of potatoes that quickly rots and invaded by bacteria.
  • It is devastating to potatoes and once set in it is very difficult to stop. The potato blight pathogen (a fungus-like organisms) is what caused the Irish Potato Famine.
  • There are ways to protect your potatoes from blight. Earthing up your potatoes, practising crop rotation and planting First earlies that can be harvested early help reduce the risk of infections. There is help at hand for gardeners regionally with the aid of Blightwatch, who track and forecast when blight is active in your region. 

Top Tips

  • Potatoes are traditionally planted on Good Friday. In general the further north you are, the later you plant your potatoes.
  • Pests and diseases of potatoes to look out for are; potato blackleg (a bacterial disease that causes rotting at the base of the stem), potato scab (a disease casing scab-like lesions on potatoes skin), potato rot (occurs after a very wet growing season or in very wet soil) and slugs (who love to munch holes in potatoes as they grow in the ground).