Some folks talk about new potatoes as if they’re a special variety to grow. Although small red tubers are frequently equated with new potatoes, any freshly dug spuds that haven’t been stored fall into the category. Hands down, to my way of thinking, new potatoes are a key reason to have a home garden, and here in mid-July the harvest has begun.
Many folks bypass potatoes, particularly if their home garden is small. But there are ways to include spuds — growing them in containers is one solution, whether five-gallon pails, barrels or small raised beds. There are also commercially available “potato bags,” specialized fabric pots that make it possible to grow tubers in almost any sunny location. There may not be enough to store away, but a supply of fresh potatoes during the summer months is a worthy goal.
A native of the mountain regions of South America, Solanum tuberosum is essentially a cool-weather crop that thrives on plenty of moisture and an acid soil. Over 4,000 varieties grow wild in their native Andes, where potatoes were domesticated by the Incas 7,000 to 10,000 years ago. Today potatoes are the world’s third-largest food crop in terms of human consumption, after wheat and rice.
The scope of varieties from which to choose is wide, though only several dozen are grown across the U.S. for commercial production. As for the home garden, outfits like the Maine Potato Lady are a rich resource of specialty varieties, along with other Maine-based companies like Fedco Seeds and Johnny’s Selected Seeds. Locally, Paris Farmer’s Union carries an excellent selection of seed potatoes in the spring including fingerlings, at a fraction of the cost of ordering through the mail.
Specialty potatoes are unusual, and in some cases of extraordinary flavor, color and quality. And while they deserve a spot in the garden, gourmet varieties do not replace main crop regional favorites. Katahdin is still a great potato, remarkably adaptable over a wide range of conditions, and yields spuds unusually high in Vitamin C. Kennebec, with its resistant to late blight, is another good bet, and a summer does not go by without my planting Red Norland, an early maturing, prolific red-skinned variety perfect as new potatoes. As for baking, Gold Rush is my hands-down favorite russet.
Regardless of the variety, potatoes thrive in a well-drained soil rich in organic matter and a weed-free environment. Avoid planting on freshly limed or manured ground, since both encourage the presence of scab. There are ways to ensure a high humus level without fresh manure, however. One is to prepare the potato bed the fall before, digging in ample compost, leaves or rotted manure. Another is to plant the area with a cover crop in the early fall, turning the green manure under as early in the spring as the soil can be worked.
Growing potatoes also means coping with their nemesis, the Colorado potato beetle. Adult beetles over-winter in the garden, burying themselves in soil to weather the cold months. With warm spring temperatures they resurface, finding host plants to eat until mating time in late May. Females lay several dozen bright orange eggs on the underside of potato leaves and adjacent foliage, which hatch in a week’s time. The beetles are prolific, and continue to eat and lay eggs throughout the season.
Larvae emerge as grotesque reddish-orange eating machines, defoliating whole rows in a matter of days. The first hatch often coincides with flowering, and unless the damage is minimized, the crop is stunted or lost. Dealing rationally with the infestation, rather than reaching for heavy duty insecticides, is a challenge.
But there are low-impact, effective solutions, though they require regular monitoring, hand work and persistence, key elements to the practice known as Integrated Pest Management. IPM is an ecological approach to pest control that combines different techniques to maintain pests below damaging levels. By practicing IPM, growers and gardeners protect the environment while maintaining food quality.
In the case of potatoes, cultural practices form the frontline. Crop rotation is critical, though for home gardeners with limited space, this is a challenge. Whenever possible plant potatoes on new ground. A very effective tool in controlling damage is exclusion, the use of floating row covers at planting time. Certainly the occasional beetle emerges underneath, but they are few and far between and can be removed.
Also effective is picking off the adult beetles. It sounds labor intensive and a little grim — and it is. But potato beetles are voracious eaters, and checking daily for adults or egg clusters and removing them can have a real impact.
Larvae emergence is inevitable, but there are effective treatments with low toxicity to humans and benign pollinators. Spinosad, marketed under several names, is a natural substance made by soil bacteria that is toxic to certain insects. Spinosad affects the nervous system of insects that consume it, though it can take several days to control the larvae. Available as a dust or spray, some Spinosad products are approved for organic agriculture. Neem oil is another control product with low toxicity.
The bad news is that Colorado potato beetles are as inevitable as changes in New England weather. The silver lining is that with consistent monitoring and a tool chest of cultural practices, they can be controlled. The end result is well worth while — new potatoes. There’s nothing like them.
Ann Bennett writes and gardens on a hillside farm in Jackson.