Global: At 70×30 cm Spacing, 60 t/ha of Potatoes Needs About 1.26 kg per Plant
A 70×30 cm layout gives about 47,600 plants per hectare. That means 0.84 kg per plant for 40 t/ha and 1.26 kg for 60 t/ha. Research shows how stems and seed size decide tuber numbers.
How many kilograms must one potato plant give to reach a target yield? The answer starts with simple arithmetic. With 70 cm between rows and 30 cm between plants in the row, each plant occupies 0.21 square metres. One hectare then holds about 47,600 plants, or 4.76 plants per square metre (our calculation).
To harvest 40 tonnes per hectare at this spacing, each plant must give about 0.84 kg of tubers. For 60 tonnes per hectare, each plant must give about 1.26 kg. If the average marketable tuber weighs 100 g, that means roughly 8–9 tubers per plant for 40 t/ha and 12–13 tubers per plant for 60 t/ha (our calculation). Missing plants raise the load on the plants that remain.
What research says about stems and tubers
Agronomists usually count stems, not plants, because one seed tuber can produce several main stems. According to the potato knowledge platform PotatoWorld, a common ware practice is about 4 plants per square metre, using seed of around 60 g and a seed rate of around 2.5 t/ha. Four well-sprouted seed tubers of 55 g per square metre give about 16 stems per square metre. The same source says stem numbers rise from around 10 to 40 per square metre as the seed rate rises from 500 to 4,000 kg per hectare. Larger seed, from 10 g to 120 g, raises tuber numbers from about 10 to 20 per plant.
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A 2024 study by Wageningen University researchers in Field Crops Research tested 6.7, 13.3 and 20 main stems per square metre. Crops from seedling tubers set 68–119 tubers per square metre, with an average tuber weight of 36–53 g. More stems gave more tubers, but smaller ones.
For seed crops the targets are higher. The New Brunswick agriculture department in Canada gives a requirement of over 30 stems per square metre, with 91 cm rows and 15–40 cm between plants.
Why it matters
A yield target is only real if it is converted into kilograms per plant and tubers per plant. At 47,600 plants per hectare, 60 t/ha needs about 1.26 kg from every plant. That requires a full stand, the right stem number and enough water and nitrogen to fill 12 or more tubers. Growers can check this with a simple test dig: count plants on 10 metres of row, lift a few plants, and weigh the tubers.
The topic was raised by practitioners in the MAX messenger chat «КАРТОФЕЛЬ И Т.Д. (Potato etc.)», a community of more than 1,100 potato growers and industry specialists. Participants are not named. Join the discussion.
Photo: Rows of potatoes in a field (illustrative). Richard Sutcliffe / Wikimedia Commons, CC BY-SA 2.0
