Potatoes are such a good vegetable to grow in our gardens. They are pretty simple to grow for the most part and once you get your harvest, potatoes will keep in the refrigerator for quite a while. That’s a win-win in my book.

One thing that can be confusing for new potato growers is the term “seed potatoes.” Seed potatoes are potatoes that are grown to serve as seed potatoes rather than dinner. If you’ve not grown potatoes before, you’ve likely had the experience of keeping potatoes in your pantry for too long and they started to sprout. That is what we want seed potatoes to do.

While you can use grocery store potatoes, oftentimes they have been treated to prevent them from sprouting because most people would prefer to purchase potatoes at the grocery store that have not sprouted. Sprouted potatoes would indicate that they are not the freshest if you will. Seed potatoes, on the other hand, have been grown for the purpose of becoming seed potatoes, so they have not been treated.

The exception to this rule would be organic potatoes from the grocery store. These potatoes can sometimes work, but you’ll need to get them soon enough to give them time to sprout. More often than not, you’re better off if you just buy seed potatoes.

Local vendors should have a good supply of seed potatoes pretty soon or if you are a mail order shopper, seed potatoes are available for order now with shipping starting in early February. A lot of the mail order suppliers sell out early, so now would be the time to get on that.

Once you have your seed potatoes, you’ll want to cut them into about 1.25-inch chunks with each chunk containing at least one “eye” or sprout. You’ll want to do this about a week before you plan to plant so the exposed portion of the potato can dry out and kind of crust over. During all of this, be careful not to knock off the sprout.

As tradition has it, St. Patrick’s Day is the day to plant potatoes. However, you can plant potatoes a little bit earlier if you prefer. Soil temperatures just need to be around 40 to 45 degrees to plant potatoes. You can check soil temperatures in your area with a soil temperature gauge, or you can visit mesonet.org to get an abundance of weather info for Oklahoma, including soil temperatures throughout the state.

To plant your seed potatoes, dig a hole about 3 to 5 inches deep for each one and as a rule, about 10 inches apart. Sprinkle a little nitrogen fertilizer near your plant about a month after planting and again about 2 weeks after that. You don’t need to get the fertilizer right up next to the plant because nitrogen is what we call a mobile nutrient because it moves easily through the soil.

Next, you’re going to do some “hilling”. Hilling is how we get more potatoes from each plant. Here’s what that means. When your potato plants get about a foot tall, mound up some dirt around the stem, maybe 2 to 3 inches worth making a little mound around the plant. This is called a “hill.” As the plants grow, do this one or two more times. The theory behind this is that as you bury some of the plant stem, you are creating more places where potatoes can grow. It’s just a way to increase the number of potatoes you will get from your plant.

If you are so inclined, you can approach this from another angle. Some potato growers dig a deeper trench to plant their seed potatoes. For example, you could dig a shallow trench about a foot deep and place your seed potatoes at the bottom of this trench but only cover them up with about 3 or 4 inches of soil. As they grow, just fill in the trench a little bit each time until you reach soil level. You’ll get similar results so it’s up to you how you plan to approach this.

Grow bags also work well for potatoes. If using grow bags, fold the bag down to a shallow bag to start. Place a little soil in the bag, then your seed potatoes, and then cover with 3-4 inches of soil. As the potatoes grow, unfold the bag, and add more soil. Once again, a different strategy to accomplish the same outcome.

Potato plants need about an inch of water a week but don’t keep the soil soggy. This will stress the plants and likely diminish your potential harvest.

New potatoes can be harvested about 7 to 8 weeks after planting but to get those nice big potatoes, you going to need to wait 90 to 120 days to harvest.

One of the questions that new gardeners ask is “how do I know when it’s time to harvest my potatoes?” There is actually a pretty simple answer to that question: wait until the plant turns brown. Once this happens your potatoes have grown all they are going to grow and its harvest time.

When you dig up your potatoes, shake off the dirt but don’t wash them. Keep them in a well-ventilated spot to allow the skin to set. For best results they should be kept in a dark, cool spot and allowed to cure for ten days or so.

If your potatoes have areas where the skin is green, remove those portions before eating. The green skin is an indicator that they have been exposed to air and when exposed to air while growing, potatoes can develop a toxin called solanine. Solanine will give your gastrointestinal system fits, so avoid green potatoes. See you in the garden.

You can get answers to all your gardening questions by calling the Tulsa Master Gardeners Help Line at 918-746-3701, dropping by our Diagnostic Center at 4116 E. 15th Street, or by emailing us at mg@tulsamastergardeners.org. Photo: Tom Ingram