If you’re in the Northern hemisphere, now is the time to get seed potatoes in the ground so that they have time to mature by late summer/early autumn. With that in mind, I thought now would be a great time for a post about how to grow potatoes! If you’re interested in no-dig growing, check out my post on success with no-dig spuds.
Growing potatoes is a really good introduction to growing your own food and remains a thrill even for experience gardeners. I think it’s a combination of the fact that for most people, potatoes are a relatively problem free crop, even with blight in maincrop potatoes it’s often possible to harvest the potatoes before the tubers are affected, and the excitement of waiting a few months and seeing all the growth above ground before digging into the soil and uncovering a golden bounty!
Potatoes can be a little space intensive and they are cheap to buy, however the variety available to home gardeners is huge compared with what you can buy in the shops and the taste is far better.
So, if you’re new to vegetable growing or just looking for a simple step-by-step process to follow, here’s your guide to growing potatoes!
How to Grow Potatoes: Things to Know Before You Grow
Types of potato
There are three main categories of potatoes: first early, second early and maincrop potatoes. The terms indicate when they will be planted, their uses and when they will be harvested. Typically, first early potatoes are what you would think of as ‘new’ or ‘salad’ potatoes. They tend to be smaller and waxier and have a delicious potato flavour with a thin skin. They don’t store as well so will need to be used within a few weeks of harvest. They are planted earlier and tend to be ready by early to mid-summer.
Second earlies are planted slightly after first earlies, and can be more similar to first earlies, or more multi-purpose and ‘fluffier’ when cooked. They will still tend to be smaller, and again should not be stored for a long period. They help to bridge the gap between first earlies and maincrops if you want fresh potatoes throughout the summer.
Maincrop potatoes are planted last, usually by mid/late April and will be harvested at the end of summer or early autumn. The yield from these plants is usually bigger, and the potatoes themselves are often larger. This is typically the category where you will find potatoes suitable for baking and mashing but waxier varieties are also available if you prefer that texture. If left to cure (either underground once the leaves have been removed or in a cool, dark place, the skins will harden a little and they will store much longer, for several months in a hessian sack somewhere dark and dry. Maincrop potatoes are the most likely to suffer from blight as this usually appears at the end of the summer, so if you live in an area badly affected, you may prefer to grow early potatoes. However, it is often possible to remove blight affected foliage before the tubers are affected, but they may not be as large or store as well.
What to Buy
You will be buying ‘seed potatoes’. These are potatoes that have been selected as a good size and quality for the variety, and from disease-free stock. It is possible to plant potatoes from the supermarket, however you will not know how old they are, how they have been stored or if any chemicals have been used on them, and so the results are likely to be variable at best. It really is worth buying seed potatoes. Aside from first early, second early and maincrop, you can select your seed potatoes based on cooking quality. Most retailers will include information of the texture of the potato and whether it is best for boiling/mashing/roasting etc. If you are planning to grow only a small number of potatoes, you may want to look for a good ‘all-rounder’.
Preparing to Plant
Little preparation is required before planting potatoes. I have often planted potatoes into ground that has been previously uncultivated as they help to break up the ground, making it easier to plant in the following year.
You will probably come across the term ‘chitting’ in relation to growing potatoes. This simply means placing your seed potatoes in a bright place (a sunny windowsill works well, I chit mine in my east-facing enclosed porch) and allowing the sprouts, or eyes, to grow. They will be strong and stubby rather than pale and long as they would be if sprouted in the dark. There is much debate over whether chitting is necessary, personally I do it because it helps me conquer my impatience over getting growing in late winter at a time when there is little else to be done for the vegetable garden. However, if you’re buying your seed potatoes in March or April, don’t worry if you haven’t got time to chit them before planting, they will be fine!
How to Grow Potatoes
The growing requirements for all potato categories is essentially the same: if planting a lot of potatoes, I suggest digging a trench, but if you are only planting a few, you can dig a small hole for each potato instead.
For first and second earlies, I recommend spacing 30 cm between each potato and between each row of potatoes (you should be able to fit nine potatoes in a 1m2 space).
For maincrop potatoes, I leave 30 cm between each potato, but 45 cm between each row.
Seed potatoes should be planted around 5 cm below the surface of the soil and then covered over.
You probably won’t need to water them at this point depending on your growing area. In March and April the soil is usually still quite wet below the surface. If the ground is frozen solid or there is standing water, hold off planting or your seed potatoes are likely to rot.
It may take several weeks before you see the first leaves peeking above ground. Once they are a few inches tall, cover the leaves and stems with more soil or straw/dried grass clippings – this is called ‘mounding up’. If there is excess soil around the potatoes, you can just use this to cover them, otherwise filling a small plant pot with soil and tipping it over the top of the potato works well. Last year, I used straw from some tree packaging and that worked brilliantly on our maincrops. Do this two or three times as the leaves reemerge and then allow to grow without further covering.
Potatoes are a relatively low-water crop. I suggest watering a few weeks before harvesting or when the flowers appear. This is when the tubers will be putting on the most growth and need the most water to swell to a good size. If you’re having a wet summer, this may not be necessary.
Harvesting
The moment we’ve all been waiting for! Harvesting potatoes is exciting even for experienced gardeners. It also makes a great introduction to gardening for children, letting them get their hands dirty and search for treasure beneath the soil.
First and second earlies are usually ready to harvest once the flowers have died off or around three months after planting (mid-June if planted in mid-March for example). Some gardeners suggest cutting off the flowers as they appear so that the plant puts more energy into the tubers, but I haven’t seen much evidence that this has a big impact. If you’ve done it and noticed a difference, let me know in the comments!
Main crop potatoes are usually harvested in late summer or early autumn, depending on when they went in the ground and your growing conditions. For maincrops, wait until the foliage has yellowed and died back before harvesting. The exception here is if you notice blight on the foliage, in which case the foliage should be cut back and the crop harvested immediately to stop the blight spreading to the tubers.
This year, the varieties I’m growing are: Pentland Javelin (1st early); Kestrel (2nd early); Picasso (main crop); and Marvel (main crop). I bought them from Simply Seed, where I also buy my onion sets and garlic and you can still pick up seed potatoes although at this point in the season, varieties may be limited.
Are you growing your own potatoes this year? Which varieties are you trying? If you have any favourite potato varieties or recipes I’d love to hear about them and I’ll be adding my favourite to the blog soon so check back for some great ways to use your spuds.
