How to Plant, Hill and Harvest Potatoes
Shift your garden into versatile gear by planting potatoes. These humble subterranean offerings adapt to various preparations with ease. Scalloped, whipped, baked, fried—potatoes are the quick-change artist of the veggie patch. Growing these underground jewels isn’t difficult, and you can make the process even easier by following a few simple steps.
In warmest regions, sow potatoes in fall. Southern gardeners tuck spuds into soil in late winter, while cooler areas plant in early spring, about three weeks before the last frost. Potatoes have big appetites and thrive in compost-enriched soil. For clay soils, add compost to improve drainage and prevent waterlogged soils, which rot potatoes.
Sow seed potatoes 3 inches deep and 12 inches apart. For traditional row plantings, keep rows three to four feet apart. In beds using intensive planting methods, sow potatoes 12 inches apart in staggered rows.
As potato stems grow, you’ll gather soil around stems, covering roughly one-half to two-thirds of the exposed stem and leaves. This process is called "hilling" because you end up creating hills of soil around stems. The tasty spuds form from the root system that grows out and up from the planted potato—not in the soil below the planted potato.
Knowing this, you might want to dig your planting furrow up to 6 inches deep, keeping extra soil from the furrow stacked alongside the planted row. As stems grow, use a hoe to heap that soil around stems. Typically the first hilling occurs when stems reach 6 to 8 inches tall. Most gardeners make one to two hillings, but you can continue to hill plants throughout the entire growing season.
The hardest part of hilling potatoes repeatedly is having enough soil on hand, especially if you garden in raised beds using intensive growing methods. One option is removing the top 12 inches of soil prior to planting and stashing it in plastic bags nearby (not too far—it’s heavy). You can also hill using a blend of homegrown compost and bagged potting soil or topsoil. Save soil from container gardens at the end of the growing season to blend with compost for this purpose.
Simplify the hilling process by substituting straw for soil. Add straw frequently to maintain consistent levels. With this method, harvesting is a cinch—no digging is required. Simply pull straw away to reveal tubers. Whether you use soil or straw, it’s vital to keep potato roots moist from the time plants flower until roughly two weeks before harvest. Potatoes have shallow roots and are sensitive to fluctuating soil moisture. When you’re hilling with soil, it’s a good idea to add a mulch layer.
Harvest new potatoes a couple months after planting by pulling a plant or two, or by feeling around in soil or straw and pulling a few young spuds. Gather the main harvest when plant tops die back, or count the number of days your variety needs to mature after planting and harvest then. Let soil dry a bit before harvesting so it isn’t caked on tubers.
Don’t wash newly dug potatoes. Instead, give them a simple brush with gloved hands. Freshly harvested potatoes need time to cure and form dried skins before storing. Cure by arranging spuds in a single layer for about two weeks at room temperature. After curing, expect potatoes to store for six months or more in a cool, dark place.