You should be planting your early potatoes this week, so here’s a tip to make it easier for you: Plant extra-small seed potatoes, and plant whole potatoes rather than cut-up pieces. There are several reasons why.
First, it’s a fact that the more stems your potato plants have, and the lower they start on the plant, the better your crop is likely to be. That means you should have more “eyes” (meaning sprout buds) on each seed potato. Extra-small seed potatoes have more eyes than cut-up small pieces.
Second, cut-up pieces are more likely to rot in your garden than whole seed potatoes. Protecting cut pieces from rot requires dusting the pieces with powdered sulfur, and letting them dry out for a day or two before planting. This is an extra step and more work for you than planting small whole potatoes. For these two reasons, we’ve switched to carrying only extra-small seed potatoes at our nursery. The labor savings alone are well worth the small difference in cost.
Plant your potatoes where you haven’t added lime or manure for at least a year. Manure and lime invite scab by reducing the acidity of soil, and potatoes like acid soil.
Till deeply to make trenching easier, and then dig a trench six to eight inches deep. Sprinkle 5-10-5 fertilizer along the bottom, and then cover the fertilizer with two to three 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 potatoes one foot apart, cover them with four more inches of soil and tamp it gently.
Once the plants have sprouted three to five inches tall, it’s time to “hill” around them with loose soil. Repeated hilling discourages weeds. If you cover the plants a little bit they’ll pop right through in a day or two. To get a good crop, you must continue to add soil, making sure potatoes aren’t exposed to the sun. Hilling is also the way to protect the young plants from frost, so hill your plants if you have a late-frost warning. Each time, cover most of the potato vine to encourage additional roots to form.
Here are a few hints to improve your potato crop this year: 1) Water generously during the third and fourth week after plants emerge increases yield. This is when they set their new tubers; 2) the more stems that come direct from the ground and form a leaf canopy, the higher the yield; 3) the longer the leaves remain, the higher the potato yield; and 4) if you wait to harvest for three to four weeks after the tops die back, your potatoes will keep longer. For potatoes you eat fresh, harvest sooner.
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, “Captain Jack’s Deadbug Brew” (for killing potato beetles, and you WILL have potato beetles), and an ounce of garden sulfur.
We recommend dusting with sulfur, because sulfur protects from rot, and because it gives new sprouts a quick acid charge. It’s not a good idea to give potatoes nitrogen, except to stimulate the sprouts in the very beginning. Sulfur does this perfectly.
Steve Boehme and his wife, Marjorie, own GoodSeed Nursery & Landscape, located at 9736 Tri-County Highway, near Winchester. More information is available at goodseedfarm.com or by calling 937-587-7021.