Grow Perfect Potatoes Every Time

15 March 2023, written by Benedict Vanheems

Everybody loves the sensational spud! For me these nuggets of goodness epitomise the joy of gardening. They’re satisfying to plant, grow at a rate of knots, and digging up that buried treasure when it’s time to harvest is a real highlight of the gardening year!

Whether you want to grow your potatoes in the ground, in containers, or even in straw, my top tips will practically guarantee perfect potatoes - every time!

Choosing the Right Type of Potato

Your journey to splendid spuds starts with choosing the right variety, so you’ll first need to decide how you want to cook them. Floury types are perfect for roasting or mashing, while a firm, waxy potato is superb boiled or as salad potatoes.

As well as deciding on the texture and flavour of your potatoes, you’ll need to make a call on when you want to harvest them, and for this, potatoes are divided into three categories.

First earlies are the first to be planted, from earlyish spring. First earlies grow really quickly, ready to harvest by early summer. Next up are second earlies, which take a bit longer to grow and are typically lifted up from the second half of summer. And then you have your maincrops, which are planted a few weeks after earlies in mid spring to dig up from late summer and throughout the autumn. Maincrops take the longest time to grow but are the best for storing, lasting for several months in the right conditions, which means the tantalising prospect of garden-grown spuds in the depths of winter.

Chitting Potatoes

Potatoes for planting are called ‘seed potatoes’ and usually sold in bags or netting. Some areas run special ‘Potato Days’ where a wide range of varieties are sold as individual seed potatoes – ideal if you have a smaller garden but want to try out a few different varieties. The moment you get them, break them free, lay them out in a tray and pop them somewhere bright and frost-free to sprout – a process called ‘chitting’. This helps speed things along so that by the time they’re planted they’re primed and itching to send out roots.

Have a look at a seed potato and you’ll notice these tiny dimples, called ‘eyes’, where the sprouts emerge from. The end with the most eyes should face upwards. Egg boxes are great for supporting the potatoes so they don’t roll over.

You can also cut up seed potatoes into two or more pieces to increase your stock for free! Make sure there are a couple of dimples or shoots on each, then leave them to dry for a day or two after cutting before planting them.

Chitted seed potatoes produce stout, stocky sprouts, quite unlike the long, pale shoots you get when potatoes are left in the dark. If you haven’t had a chance to chit your potatoes and it’s already time to plant don’t worry – just get them in the ground. Chitting is ideal but not absolutely essential. One thing that is crucial, however, is to use these purpose-sold seed potatoes because they’ll be disease- and pest-free, giving you an easy step forward to those perfect potatoes.

“Planting — If your soil isn't too heavy, planting potatoes in individual holes works well

How to Plant Your Potatoes

If you’re growing in the ground or in raised beds, spread compost across the surface to a depth of around an inch (3cm). Potatoes are hungry plants, so this extra nourishment will help to support good soil fertility and a strong harvest.

Raised beds are generally warmer than the surrounding ground because they are freer draining, and this should make all the difference if you’re planting early in the season.

To plant, simply dig a hole for each seed potato and then, to give the potato a real boost, add in a little slow-release organic fertiliser – I like to use chicken manure pellets – and then pop in the potato, sprouts pointing up. Cover back over so there’s a good depth of soil sitting over the top of it – aim for about 6in (15cm) if you can.

Taste and speed rather than size are my priorities for first earlies, so I plant them about 16in (40cm) apart in both directions, but if you are after bigger potatoes you could space them a little further apart. Maincrop potatoes need more space to stretch their legs, so space them at least 18in (45cm) apart.

Another option is to dig V-shaped trenches 2-2.5ft (60-75cm) apart. Lay a nourishing cushion of garden compost along the bottom along with a scattering of organic fertiliser, then set the tubers into position about a foot (30cm) apart. Then just fill back in with soil. I don’t think it makes a huge difference which way you plant – holes or trenches – so do whatever’s easiest in the space you have.

One other option is to simply nestle your potatoes down into the soil surface then cover them with a thick layer of straw. I’ve done this before and it worked really well, but if you have lots of slugs in your garden just be aware that straw could give slugs more places to lurk.

“Frosted — Late frosts can damage potato foliage

Growing Potatoes

Potatoes aren’t fussy vegetables, which makes them a fab choice for first-time growers. They do well in most soils and almost always produce plenty of tubers to go hunting for at harvest time. That said, there are a few things you can do to elevate your crop.

Firstly, water! This is really important because potatoes are lush and leafy plants, and those tubers take a lot of effort to swell. So if it’s dry, water thoroughly. The other thing you can do is ‘hill’ your potatoes by banking up the soil around the stems as they grow. This creates more soil volume for the tubers to grow into, while reducing the risk of spuds making their way to the surface and turning green. Just draw up the soil with a hoe every time the stems get to around 6-8in (15-20cm) tall so that just the very tops are left poking out. Continue doing this in stages until you can no longer draw up any more soil, or the foliage closes over between the rows.

If you’re growing your potatoes in a smaller raised bed, it may be easier to simply top up with organic matter over the whole area.

Late frosts can damage the young foliage. Frost-bitten plants usually have enough energy to shake off any damage, but it can set plants back nonetheless. So if a frost is forecast and potatoes stand to get clobbered, do whatever you can to protect them. Cover the area in a few layers of warming horticultural fleece, cover clusters of shoots with pots, or draw up the soil to bury the young shoots.

Potatoes in Pots

Not everyone has garden space for potatoes, but a great alternative is to plant potatoes into containers such as large pots, old compost bags or purpose-sold potato sacks. This is also a great way to enjoy an early harvest of spuds because you can start them off under cover or somewhere sheltered..

Fill the bottom of your pot or sack with about 4in (10cm) of potting mix then lay one or two potatoes on top and cover. Once the foliage is growing, add in more potting mix, a bit at a time, to hill them up until the soil level reaches the top – at which point the foliage almost seems to explode in size, capturing all that solar energy and feeding it down into the developing tubers below. You can keep them in a greenhouse or hoop house for an earlier harvest, but any sheltered and sunny spot would do too.

Do keep your plants really well watered, especially in warmer weather, as this really will make all the difference in achieving a good crop.

Dodge Potato Diseases: Scab and Blight

We’ve chosen, chitted, planted and hilled our precious potatoes. We’re almost home and dry! But before we cross the finishing line let’s look at a couple of diseases that could scupper our mission for perfect potatoes.

The most common is scab, which causes rough, scabby patches on the skin. These can be peeled off along with the skin so it’s not disastrous. But scabby potatoes ain’t half ugly! So avoid scab in the first place by watering to keep the soil consistently moist at the critical time when tubers are developing – basically once the foliage has started to bush out. Adding compost or other organic matter to the soil before planting should help improve water retention too. It’s also worth seeking out scab-resistant varieties.

Potato blight, or late blight, is a little trickier to dodge. It strikes after a period of warm, wet weather, seemingly out of the blue. Blight causes dark patches on the leaves as it takes hold, then spreads with devastating speed until it kills off your entire crop. There are a few blight-resistant varieties available, but the choice is very limited. The good news is that early varieties are usually harvested before the blight arrives later in summer. Check regularly and if you do spot the tell-tale signs of blight, act fast to cut back the foliage before it spreads to the tubers below ground. Harvest them as soon as possible.

Harvesting Potatoes

Harvesting at the right stage prevents tubers from sitting in the soil for too long and decreases the chances of a slug or disease attack, particularly for maincrop spuds.

Earlies are the first to be lifted, usually while the plants are still in flower. Your tubers should be about the size of a hen’s egg or a touch bigger, but really it’s up to you how big you want them. Use a fork and work your way in from the edge of the plant, taking care to avoid stabbing any potatoes! Once you’ve loosened the plants you can also lift them up by the stem to pull out most of the spuds, but be sure to dig around in the soil for any you’ve missed.

Dig up maincrop spuds once the foliage is dying back towards the end of the growing season. I find it easier to cut back the foliage before digging up the potatoes on a dry day. Leave the potatoes on the soil surface for a few hours so the skin can dry off a bit. Don’t leave them there any longer or they may start to turn green. Once they’ve dried off, pack them up into breathable sacks or sturdy cardboard boxes to store somewhere dark, cool, but frost-free. Only store potatoes that are free of bruises, disease or damage, as you don’t want problems to spread in storage. Check on stored potatoes every few weeks and remove any that are starting to spoil.