These are a little small, but Steve couldn't wait for them to reach full size.
Parsnips are grown for their thick, tapered, white rootstock which is used much like the root of the closely related carrot (Daucus carota). The above ground plant stands about a foot (30 cm) or two (60 cm) tall, with carrotlike leaves that are pinnate with 5-11 segments. The parsnip is actually a biennial, growing its foliage and storage-organ root in its first year, and flowering and dying the second year. Like other members of the Apiaceae (a.k.a. Umbeliferae), the parsnip's flowers are arranged in compound umbels. Cornucopia II lists 15 varieties of parsnip available from seed sources, but most companies offer only Harris Model and Hollow Crown.
Location Pastinaca sativa occurs naturally throughout northern Europe and western Asia, where it grows in open grasslands, often on calcareous soils. The parsnip has escaped cultivation and become an invasive weed in much of North America except the southeastern states. In Ohio, parsnip is listed as a prohibited noxious weed. Note, however, that the feral or wild parsnip, although the same species, is not quite the same as the cultivated form. Wild parsnips have smaller, less flavorful rootstocks than those grown for food.
The slow growing parsnip does best with a long, cool growing season. The starches in the root are converted to sugars when temperatures drop to freezing and below. The sweetest roots are harvested in early spring from seeds that were planted the previous autumn. Light: You will get the biggest crop when parsnips are grown in full sun. Moisture: Parsnips do best in a slightly moisture retentive soil, but they do not need to be watered much since the enlarged rootstock carries them through dry spells. Parsnips don't do well in hot, dry climates. Hardiness: USDA Zones 3-9. Parsnips are grown as cool season annuals and can tolerate temperatures well below freezing. Propagation: Plant parsnip seeds a half-inch (1.75 cm) deep, and expect germination in 2-3 weeks. Parsnip seeds are notoriously short lived. You will usually need to get fresh seeds each season, although I have had some success with year-old seeds that had been stored in the refrigerator. The most perfectly shaped parsnips are grown by creating a conical planting hole in the ground with a crow bar or dibble, filling the hole with a fine potting mix, and then planting the parsnip seed near the top of the hole.
Parsnips growing where the butterbeans were a few months earlier.
Parsnips do best in organically rich, deeply spaded soils. The roots can get up to 18 in (45 cm) long if the soil is friable and well fertilized with rotted manure and compost. Don't overdo the nitrogen, though, as this will encourage more leafy growth at the expense of the rootstock, and cause the rootstock to split. If the soil is too clayey the roots may fork; if it's too sandy the roots will be "hairy" with numerous fibrous side roots instead of a single large main root.
Home grown parsnips are so much better than the shriveled and dried corpses you find at the supermarket. Home grown parsnips (pulled after at least one frost) are crisper and more flavorful. They have a sweet, almost nutty flavor and are especially delectable sauteed in butter. Before the potato conquered Europe in the sixteenth century, the parsnip was the dominant starchy food, served with most meals. Parsnips are similar to potatoes, but much sweeter, and like potatoes, they can be mashed, fried, boiled or baked. Some cooks regularly include a parsnip or two in their mashed potatoes. Raw parsnips are delicious shredded in salads or cole slaw, or sliced and served with a cheese dip. As with other members of the parsley family, parsnip foliage is eaten by the larvae of the black swallowtail butterfly.