The soil temperature is above fifty and dandelions are blooming, so it is time to get potatoes in the ground. I got four rows planted this morning with sprouted seed potatoes from the Farmer’s Coop. “Seed potatoes” are misnamed, they are not seeds but tubers certified to be disease-free and therefore good for replanting. Raising potatoes from actual seeds is almost never done.

Sprouted potato. When left in the light for a week or two, the potato breaks its dormancy and sprouts little shoots from "eyes." The potato is a swollen stem; the "eyes" are the nodes, like the buds on the side of a tree branch.

Eye-to-eye with a sprouted eye. Baby leaves are visible atop an expanding mass of tissue that will ultimately form the stems and roots of the new plant.

The date came to me as I planted: St Patrick’s Day. Of course, the Irish potato famine also came to mind, a disaster made possible by the combined forces of a genetically uniform potato crop (only one clone, the Lumper potato, was grown, making the crop very vulnerable), an attack by Phytophthora infestans (a water mold), and the policies of the British government.

Phytophthora is still a major pest of many crops worldwide. It caused the massive tomato die-off in the eastern U. S. in 2009. Its disease potential increased recently as new strains arrived in North America and Europe, allowing the species to engage in sexual reproduction (previously it had been breeding only asexually) and thus create new genetic combinations with which to attack its hosts.