While planted in spring, parsnips are a considered a winter vegetable. A prolonged freeze converts the starchy root into the sweet tasting vegetable that is prized on many dinner tables. Like its close relative the carrot, parsnips have a long conical root. Unlike the carrot, parsnips are white or off-white in color and also have a larger diameter, especially near the leaves. Plant many more seeds than desired parsnips as they germinate poorly and many of the seeds won't be viable at all.
Prepare a well drained bed after the ground has thawed in spring. Till the soil to an 18-inch depth using a power tiller and remove any large rocks or roots that you find.
Apply a 3 inch layer of compost on top the bed and till it in to aid soil nutrition and drainage. Till it into the top 6 inches of the soil.
Sow seeds at a rate of three per inch in rows 18 inches apart. Sow on the soil surface and cover with ½ inch of compost or soil.
Keep the soil moist but not soaking wet during germination, which takes 4 weeks or more. Use a mist attachment on the hose to avoid washing away the small seeds.
Thin seedlings to 4 inches apart once they have their third set of leaves. Choose the healthiest seedlings and pull out the weaker ones.
Keep soil moist but not soaking wet throughout the growing season. Provide approximately 1 inch of water to the garden in a weekly deep watering.
Harvest parsnips in the fall after two to four weeks of frost. Dig up carefully with a spading fork, being cautious not to bruise or cut the parsnips.