Updated: May 31, 2020
What could be more fun than unearthing a pot of spuds with your family on Thanksgiving? This is one of the best gardening surprises, like hunting for Easter eggs only a bit more wholesome.
Because the potato is such a vigorous grower, it is happy growing in just about any kind of container so long as a few basic rules are followed. The most important rule is to match the number of seed potatoes to the size of the container you are going to grow them in.
Each potato plant needs roughly 10 litres to grow into. If you try to plant too many, the result will be very small spuds or none at all. For example, a typical garbage can would hold about four plants. Whatever container you use, make sure it has adequate drainage holes in the bottom to let excess water drain out.
Put some drainage material in the bottom of your pot, a couple inches of gravel will do, cover with a piece of permeable cloth then fill with about 4 inches of soil. Multipurpose potting soil works well, but mixing good garden soil and some compost or manure is also fine.
Space your seed potatoes, sprouts pointing up evenly throughout the container. Cover with another 4 inches of soil, then sit back and wait. As the shoots grow, continue to add further layers of soil until you reach the brim of your container.
Be sure to keep your potatoes well watered. While plants growing in the ground have lots of water to draw from, container grown plants do not. They will need regular watering especially once the foliage has filled out and some liquid fertilizer a couple of times during the growing season.
The potato foliage will continue to grow and blossom until sometime in mid to late September when the leaves will begin to turn yellow and wilt. You can begin to harvest as soon as the plants begin to flower by feeling around with your hands in the soil and pull out any that are the size of an egg. If you want bigger tubers, wait until the foliage has died down and just tip the pot over for the final surprise!