The trenching method will grow a good crop of the largest, healthiest potatoes. (Illustration by Marjorie Boehme).
By Steve Boehme

Experienced gardeners plant two crops of potatoes, in late March and again after last frost. Potato plants can survive frost if they get a little protection, so it’s time to get ready for that first planting now. Potatoes will begin to grow as soon as the soil temperature has reached 45 degrees F. The soil should be evenly moist, but not wet or soggy. We recommend using peat moss to dry wet soil; simply till it into your potato rows before planting.

Start with certified seed potatoes from a garden center or farm supply store. Grocery store spuds are chemically treated to prevent them from sprouting so they won’t usually work. Using old leftover potatoes is chancy because they can be carrying disease organisms. Cut them into chunks with 3-5 eyes apiece. Small potatoes can be planted whole.

Wet garden soil can rot your seed potatoes. To protect them from rotting, shake the pieces in a bag with an ounce or two of powdered garden sulfur, then let them dry out for a day or two before planting. If you pre-sprout potatoes before planting, it will decrease the likelihood of rot. Put them in a warm sunny place until sprouts form, then cut them into pieces before planting.

Potatoes like acid soil. Manure and lime invite scab by raising the soil PH, so pick an area where you haven’t added lime or manure for at least a year. Till deeply to make trenching easier, and then dig a trench 6-8 inches deep. Sprinkle 5-10-5 fertilizer along the bottom, and then cover the fertilizer with 2-3 inches of soil before placing the potato in the trench. If fertilizer touches the potato it can burn it and cause it to rot. Plant your potato chunks (eyes facing up) one foot apart. Now cover the potato with 4 more inches of soil and tamp it down.

Once the plants have sprouted 3 to 5 inches tall, it’s time to “hill” around them with loose soil. If you cover them a little bit they’ll pop right through in a day or two. Hilling is also the way to protect the young plants from frost, so keep an eye on the weather; hill your plants when you have a late frost warning.

Potato plants form their new tubers abovethe original seed piece. To get a good crop you must continue to add soil, making sure potatoes aren’t exposed to the sun. Repeated hilling also discourages weeds. Each time, cover most of the potato vine to encourage additional roots to form.

Here’s a shopping list for successful potato gardening: For each 100 feet of row you’ll need about five pounds of seed potatoes, three pounds of 5-10-5 fertilizer and an ounce of garden sulfur. Here are our favorite potato varieties:

EARLY

Yukon Gold: The best yellow-fleshed early potato, Yukon Gold has beautiful golden color and a rich, creamy flavor. It’s excellent baked, boiled, or mashed, and also stores well.

Red Norland: Early round red potato. Perfect for steaming or boiling, this is our favorite cooking potato and expensive to buy in stores. Very productive, scab resistant.

MID-SEASON

Red Pontiac: A large round red-skinned potato with thin, dark-red skin, deep eyes, and high yields. Red Pontiac is easy to grow and store.

Kennebec: This short oval potato has smooth pale yellow skin, shallow eyes, and white flesh. Kennebec is an excellent producer, great for baking or frying, and stores well.

LATE-MATURING

Red LaSoda: With smooth red skin, deep eyes, and white flesh, Red LaSoda is excellent for boiling and making potato salads. Possibly the best-storing red, it tolerates high temperatures and is disease-resistant.

Steve Boehme is the owner of GoodSeed Nursery & Landscape, located on Old State Route 32 three miles west of Peebles. To e-mail your landscaping questions click “Contact Us” from their website at www.goodseedfarm.com or call (937) 587-7021.