How to Plant Seed Potatoes

Seed potatoes
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Potatoes are one of the easiest vegetables to grow. All you need is a mature potato from the variety that you want. It grows vegetatively, meaning you transplant a whole or part of the actual potato. This is a seed potato. This term can be a bit confusing since they are not seeds at all. If you have ever wondered why you do not see potato seeds packets for sale, it's not that potatoes don't set seeds; rather, they do not grow from them. Potatoes do not grow true to seed or do not yield the same type of plant when grown from the seeds of the original plant.

When to Plant Seed Potatoes

Potatoes do best in full sun. They can be planted in the early spring as long as the threat of freezing ground temperatures has passed. Seed potatoes planted in soil that is too cold or soggy may rot. Generally, potatoes will not grow until the soil temperature has reached 45 degrees Fahrenheit. You can plant a second crop as late as June 15 and harvest the potatoes as late as possible.

Working With Potatoes

Potatoes are aggressively rooting plants and will produce the best crop when planted in a light, loose, well-drained soil. Potatoes prefer a slightly acid soil with a pH of 5.0 to 7.0. However, potatoes are prolific growers and often adaptable to poor soil and climate conditions.

When selecting seed potatoes, do not try growing potatoes from potatoes you buy at the grocery store. Grocery produce is often treated with a growth inhibitor, which keeps potatoes fresher longer but also prevents sprouting or stunts growth.

Organically grown potatoes may be free of growth inhibitors, but they are prone to any diseases carried over from their growth period (like ring rot or fusarium wilt). You need disease-free, certified seed potatoes. Discard any seed potatoes that have a soft spot, cracks, bruises, or signs of rotting. Even certified seed potatoes can get disease once planted, but they have the benefit of disease resistance.

Before you plant your seed potatoes, you may also decide to chit or pre-sprout your potatoes. If you decide to encourage stem growth on your potatoes, this process will add 2 to 4 weeks to the process.

Project Metrics

  • Working Time: 30 minutes
  • Total Time: 4 weeks (depending on if you chit your potatoes)
  • Material Cost: Approximately $1 per pound of seed potatoes

What You'll Need

Equipment/Tools

  • Knife

Materials

  • Seed potatoes
  • Powdered sulfur (optional)
  • Bag (optional)
  • Egg carton, tray, or screen (optional)

Instructions

  1. Chit Your Potatoes (Optional)

    Although potatoes will sprout in the dark, you will get long, pale shoots that easily break. Instead, place them in a cool spot with bright light for 2 to 4 weeks. This way, the sprouts will grow stocky, sturdy, and dark green. This process is also called greening. You can place your seed potatoes upright in an egg carton, on a tray, or screen with the bud end facing up. Do not pile them. You can start 1 month before your outdoor planting date. Potatoes will store for several months without sprouting if kept dark and at about 40 degrees Fahrenheit.

    Chitting 'King Edward' Seed Potatoes (Solanum tuberosum) 'King Edward' in Egg Carton
     Chris Burrows / Getty Images
  2. Cut the Potatoes (Optional)

    You do not need to plant a whole, intact potato. Seed potatoes can be cut into pieces. Each piece should have at least one eye each. An "eye" is the bud that sprouts into a new plant. If you are going to cut them, do it about two days before you plan to plant. This allows the pieces to callus or seal which prevents rotting and provides a barrier from soil-borne diseases while the pieces sprout and take root.

    VEGETATIVE PROPAGATION. SWEET POTATO SPROUTING NEW PLANTS FROM THE EYES. ASEXUAL REPRODUCTION. Ipomoea batatas
    Ed Reschke / Getty Images
  3. Plant the Sprouted Potatoes

Plant your potatoes as soon as the sprouts are 1/2 inch to 1 inch long. Handle the seed potatoes carefully, so the sprouts do not break off or become damaged. Plant with the sprouts facing up and cover lightly with soil.

Potatoes Planting 3
Sveta / Getty Images

Planting Seed Potato Tips

  • You do not have to chit the potatoes to get a good crop. However, you might want to chit your potatoes if you notice them beginning to sprout or if you want an earlier harvest date. If you plan to eventually cut them before planting them, chit before cutting them.
  • When planting whole seed potatoes or pieces of potatoes, in general, more eyes per piece equals more potatoes. Smaller potatoes with one or two eyes per piece mean fewer potatoes, but they will be larger.
  • To further protect your seed potatoes, you can dust them with powdered sulfur right after cutting them. Place the potatoes in a bag, add the sulfur and shake. Then lay the pieces out and let them dry for three to four days.
  • If you have to postpone planting because of weather or some other reason, move them to a cooler spot to slow down their growth. Don't wait too long; your seed potatoes may start to dehydrate and shrivel.
  • On average, one pound of seed potatoes should yield about 10 pounds of potatoes. One pound is about five to eight tubers, which should be enough to plant about a 10-foot row.