Potatoes are probably the most rewarding crop you can grow yourself if you are heading towards self-sufficiency. You put a tuber in the ground and dig up a bucketful a few months later. For half a year’s worth of potatoes (roughly 25 to 30 kilos per person) you realistically need about 10 to 15 m2, and on 25 m2 you can get towards 75 to 100 kilos in a good year. That is enough to keep a family in home-grown potatoes for a good part of the year. In this article I do the sums honestly, and walk you through the whole process: choosing varieties, chitting, planting, earthing up, keeping blight at bay, harvesting, and storing them so they last you months.
How many potatoes do you need for self-sufficiency?
Let’s start with realistic numbers, because this is where most articles get sloppy.
An adult eats around 50 kilos of fresh potatoes a year (direct consumption sits at about 53 kilos per person, not counting chips and crisps, source: agf.nl based on FAO figures). Count every potato product and you land at 80 to 90 kilos, but you are not going to grow your own chips and crisps. So work with those 50 kilos of fresh potatoes if you want to be fully self-sufficient for a whole year.
If you want half a year’s supply, you need roughly 25 to 30 kilos per person. For a family of four that is 100 to 120 kilos for six months.
And how much ground does that take? Here I have to put the popular claim of “100 to 150 kilos from 25 m2” in perspective. An average seed potato yields about 750 grams of eating potatoes (source: mooiemoestuin.nl). With roughly 3 to 4 plants per m2 you realistically get 2 to 3 kilos per m2 in a vegetable garden. In a good year, with good soil, water and healthy plants, that can rise to 4 kilos per m2. The 150 kilos from 25 m2 (that would be 6 kilos per m2) is only achievable under ideal, professional conditions. So use these figures instead:
| What you want | Amount needed | Ground (at 2-3 kg/m2) |
|---|---|---|
| Half a year, 1 person | 25-30 kg | 10-15 m2 |
| Full year, 1 person | approx. 50 kg | 20-25 m2 |
| Half a year, family of 4 | 100-120 kg | 40-50 m2 |
| Full year, family of 4 | approx. 200 kg | 70-100 m2 |
So on 25 m2 you realistically get 50 to 75 kilos, and towards 100 kilos in a bumper year. Enough for half a year for two people, or a full year for one. A nice bonus: potatoes are one of the few crops that genuinely cover your basic need for carbohydrates.
Is growing your own potatoes worth it financially?
Honest answer: purely in money terms, the gain is small. A 5-kilo bag of potatoes in the shop costs a couple of euros, and 100 kilos of your own harvest costs you money too, in seed potatoes, feed and water. Expect this range:
| Item | Cost (range) |
|---|---|
| Seed potatoes (approx. 2.5 kg for 25 m2) | 5 – 12 euros |
| Compost/feed | 5 – 15 euros |
| Fleece/covering (one-off) | 10 – 20 euros |
| Water | negligible to a few euros |
So for ten to twenty euros of seed potatoes and feed you can grow tens of kilos. The saving is real, but the actual reasons to do it are taste (a freshly lifted early is nothing like a supermarket potato), certainty about your supply, and the simple pleasure of eating from your own soil. Think of it as insurance with a tasty return, not as a savings plan.
Which potato varieties should you choose?
Potatoes are grouped in two ways: by maturity (early, second early, maincrop) and by cooking type (floury or waxy). For a good store you want a mix.
- Early varieties (90-100 days of growth) go in the ground in March and are harvested as soon as June or July. They are delicious fresh but store badly. They also tend to dodge blight, because you harvest before it strikes.
- Second earlies (100-120 days) are a solid all-rounder.
- Maincrop varieties (more than 120-150 days) give you the most kilos and are your real storage potatoes for winter.
Floury potatoes (for mash, boiling, stews) break down a bit during cooking. Waxy ones hold together and are ideal for frying, salads and roasting.
| Variety | Type | Maturity | Cooking type | Note |
|---|---|---|---|---|
| Duke of York (Eersteling) | Early | Early | Floury | Classic early, moderate storage life |
| Bintje | Second early | Second early | Floury | Top yield, but susceptible to blight |
| Nicola | Second early | Second early | Waxy | Stores well, versatile |
| Charlotte | Second early | Second early | Waxy | Popular, for salads and frying |
| Carolus / Vitabella / Sarpo Mira | Maincrop | Late | Floury to waxy | Strongly blight-resistant, ideal for storing |
My advice for self-sufficiency: take an early variety to eat fresh (Duke of York, for example), and put most of your ground into a late, blight-resistant storage variety such as Carolus or Sarpo Mira. That way you eat fresh from June and have a healthy winter reserve from autumn onwards.
Always buy certified seed potatoes, not potatoes from the supermarket. Supermarket potatoes are often treated to stop them sprouting and can carry disease. Buy your seed potatoes in February if you can.
How do you chit potatoes (and how much does it matter)?
Chitting means letting the tubers sprout before you plant them. It gives you a head start of about two weeks and therefore an earlier harvest. With early varieties in particular, it pays off.
Here is how:
1. Two to three weeks before planting, lay the tubers in an egg box or a shallow tray, with most of the “eyes” facing up.
2. Put them somewhere cool and light, around 10 degrees Celsius. Light matters: it gives you short, stubby, dark green shoots. In the dark you get long, pale, watery shoots that snap off easily and weaken the plant.
3. Plant as soon as the shoots are about 2 to 3 cm long.
Chitting is not strictly necessary, but it is one of the simplest ways to harvest earlier and harvest more. A common mistake is putting the tubers somewhere warm and dark, like a shed or utility room. That gives you exactly the weak, leggy shoots you do not want.
When and how do you plant potatoes?
Planting date. Potatoes can only go in once the risk of night frost is fading and the soil has warmed up a bit.
- Early varieties: from mid-March, provided you can cover them with fleece against late frosts. The foliage is frost-sensitive.
- Second earlies and maincrops: from mid-April to mid-May.
As a rule of thumb: only plant once the soil no longer feels properly cold and the worst of the frost is behind you. Caught out by a night frost once the foliage is up? Cover it, or briefly earth up over the young growth.
Spacing and depth. These numbers are the heart of a good harvest (sources: mooiemoestuin.nl and gardenersworldmagazine.nl):
| Variety | Spacing in the row | Row spacing | Planting depth |
|---|---|---|---|
| Early | 30-40 cm | 45-60 cm | 10-15 cm |
| Second early/maincrop | 40 cm | 60-75 cm | 10-15 cm |
Generous row spacing (towards 70-75 cm) is not wasted space: you need that room later for earthing up. Lay the tuber with the shoots facing up and cover it with 10 to 15 cm of soil. On light sandy soil you can plant a little deeper, which means less earthing up later.
Why and how should you earth up potatoes?
Earthing up means drawing loose soil up against the stems so you build a ridge. You start once the plants are about 10 to 20 cm above ground, and you repeat it a few times during the growing season.
Earthing up does three things:
1. More yield. Potatoes form along the underground stem. More soil around it means more room for tubers.
2. No green potatoes. Tubers exposed to light turn green and produce solanine, which is toxic. The layer of soil keeps them in the dark.
3. Protection. The ridge protects against late frosts and keeps rainwater carrying fungal spores away from the tubers.
A common mistake is not earthing up enough. When you lift the crop you then find part of it green and inedible, just under the surface.
Do potato towers really work (or is it a myth)?
You see them everywhere online: the potato tower or grow bag, promising tens of kilos from half a square metre, or “50% more yield per m2”. I am sceptical, and practice backs me up.
The claim that potatoes form all the way up the tower (tripling your yield or better) rarely holds up in practice. Experienced growers report time and again that the tubers sit mainly at the bottom and that the top barely sets anything. From three tubers in a grow bag you realistically get 2.5 to sometimes 5 kilos, depending on the variety. That is a decent result, but it is no miracle cure and it is not meaningfully more per plant than growing in open ground.
A tower also has two drawbacks: it dries out faster than open ground, and watering the lower layers is awkward. So you have to water more often and more deliberately.
Conclusion: a potato tower, bag or bucket is a nice solution if all you have is a balcony or patio and no garden soil. For real self-sufficiency, growing in open ground is more efficient, cheaper and more reliable. Do not believe the “60 kilos from one plant” videos.
How much water and feed do potatoes need?
Water. Potatoes like evenly moist soil, especially around flowering, because that is when the tubers set. A long dry spell then means smaller potatoes. In dry weather, water at the base of the plant and not over the foliage, because wet leaves invite blight.
Feed. Work compost or well-rotted manure into the soil before planting. Potatoes love potassium: an extra dose (sulphate of potash, for instance) around May, when the plants are about 40 cm tall, helps tuber formation (source: mooiemoestuin.nl). Go easy on nitrogen: too much gives you plenty of foliage but few tubers, and makes the plant more prone to disease.
Crop rotation. This is not optional, it is a must. Do not grow potatoes in the same spot every year, keep a rotation of at least 3 years. That stops soil-borne diseases and eelworm from building up. Do not put potatoes right next to tomatoes either, because the same fungus (phytophthora) hits both.
How do you spot and prevent blight?
Phytophthora infestans, the dreaded potato blight, is the biggest threat to your harvest. This fungal disease once caused the Irish famine, and in a vegetable garden it can wipe out all your foliage within a week.
Spotting it:
– Brown-black, wet patches on the upper side of the leaves.
– On the underside of the leaf, at the border between diseased and healthy tissue, a greyish-white fungal fuzz (most visible in damp weather).
– Elongated brown lesions on the stems, often starting in the leaf joints.
– Later, brown rotten patches in the tubers themselves.
The disease strikes mainly in warm, humid weather: above 15 degrees during the day, around 10 degrees at night, with high humidity. Then it spreads at speed (sources: rootsum.nl and mooiemoestuin.nl).
Preventing it (as far as possible without chemicals):
1. Choose resistant varieties such as Carolus, Vitabella or Sarpo Mira. Older varieties like Bintje and Roseval are the susceptible ones.
2. Plant early and chit, so the tubers already have decent size before the disease hits in summer.
3. Water at the base, not over the leaves, and leave enough space between plants so the foliage dries quickly.
4. Earth up properly so spores washed off the leaves cannot reach the tubers.
5. Clear away affected foliage straight away and put it in the general waste, not on the compost heap.
6. Keep to your crop rotation and do not plant potatoes next to tomatoes.
If it strikes anyway: remove the affected foliage immediately, or cut off all the foliage if the attack is severe. Then leave the tubers in the ground for another two to three weeks so the skins harden, and lift them after that. This stops the spores from getting at your tubers in storage. Be strict when you sort at lifting: one rotten potato infects the rest of your store.
When and how do you harvest potatoes?
The right moment depends on the type:
- Early potatoes are harvested from June or July, often around or just after flowering. These are your eat-fresh potatoes. They store badly, so lift them as you need them.
- Maincrop storage potatoes are harvested in September and October, when the foliage yellows and dies back. Do not wait until the foliage has gone completely if there is a risk of tuber rot.
For storage potatoes the rule is: once the foliage has died back, leave the tubers in the ground for another two to three weeks so the skins harden. A firm skin is the key to long storage.
Lift on a dry day with a digging fork, and push it in far enough away from the plant that you do not spear the tubers. Damaged potatoes will not keep, so use those first.
How do you store potatoes to build a 6-month supply?
This is where your self-sufficiency stands or falls. Grow them well and store them badly, and you will still be through your harvest within a month.
Dry them off first. Let the lifted potatoes dry on the surface for a few hours (not in full sun, or they will go green). Brush off the biggest clods of soil, but do not wash them: damp potatoes rot faster.
The ideal storage conditions:
| Factor | Ideal |
|---|---|
| Temperature | 4-8 degrees (2-10 degrees is still acceptable) |
| Light | Completely dark (light causes greening and solanine) |
| Moisture | Dry, but not drying out |
| Air | Well ventilated |
| Frost | Absolutely frost-free |
Store them in hessian sacks, paper sacks, cardboard boxes or airy wooden crates, somewhere dark and cool such as a cellar, an unheated utility room or a frost-free shed. Do not put them in airtight plastic bags, or they will sweat and rot.
Storage life. In these cool, dark conditions, storage times of 3 to 9 months are achievable, depending on the variety (source: tuinadvies). At a constant temperature of around 7 degrees, good storage varieties can even last towards a year. So your six-month supply is comfortably within reach, and with the right varieties you can go further.
Here is how you get to a 6-month supply:
1. Commit most of your crop to late, well-storing, resistant varieties.
2. Only harvest once the skins have hardened.
3. Sort strictly: only clean, undamaged tubers go into the store.
4. Check regularly in the first few months and pull out any rotten or sprouting ones straight away.
5. Keep the storage spot as cool and dark as you can. As soon as it gets light and warm, they start to sprout.
Common mistakes when growing potatoes
- Planting supermarket potatoes. Often treated to suppress sprouting, and they can carry disease. Use certified seed potatoes.
- Planting too early without protection. Night frost burns the young foliage. Cover with fleece.
- Not earthing up enough. Green, inedible tubers just below the surface.
- Watering over the foliage. Invites blight. Water at the base.
- The same spot every year. Builds up disease. Keep a 3-year rotation.
- Piling them up wet or unwashed in plastic. A recipe for rot. Dry them off, store them airy and dark.
- Expecting a potato tower to work miracles. Fun for the balcony, no basis for your yearly supply.
Frequently asked questions
How many potatoes do you get from one plant?
On average about 750 grams per seed potato (source: mooiemoestuin.nl). In good conditions that can rise to 1 kilo or more per plant. To be safe, count on 0.7 to 1 kilo per plant.
Can I plant potatoes from the supermarket?
Better not. They are often treated to stop them sprouting and can bring disease into your vegetable garden. Certified seed potatoes cost little and give far more reliable results.
How long can I store my own potatoes?
At 4 to 8 degrees, dark, dry and airy, 3 to 9 months is achievable, depending on the variety. Late storage varieties at a constant 7 degrees last longest. Check your store regularly for rotten ones.
Do I have to chit my potatoes?
You do not have to, but it gives you about two weeks’ head start and therefore an earlier, often bigger harvest. It pays off most with early varieties. Do it cool (10 degrees) and in the light.
What do I do if blight strikes?
Remove the affected foliage immediately (all of it if the attack is severe) and put it in the general waste, not on the compost. Then leave the tubers in the ground for another 2 to 3 weeks so the skins harden, and lift them after that. Sort strictly before you store them.
Which variety is best for self-sufficiency?
A mix: an early such as Duke of York to eat fresh early in the season, and a late, blight-resistant storage variety such as Carolus or Sarpo Mira for your winter store. That way you eat fresh from June and have months of reserve.
Want to give your potatoes (and the rest of your vegetable garden) a flying start with a good, deep raised bed? At Fred’s you will find clear building plans for raised beds and other garden projects that you can put together yourself. Have a look around at fredsdiyplans.com and build your own supply this season. Enjoy the planting and the harvest.