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If it is a single plant in aIf it is a single plant in a large pot (around 3 gallons or more) you can keep in in that pot for the year. You would want to keep it in the full sun and water regularly. if you start to see the tops of the potatoes add dirt to keep them protected from the sun. When the Green plants die off and turn brown its time to harvest. I wouldnt expect much from a single plant but you could see 3-6 potatoes depending on the type planted.

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