How to Grow: Parsnip

I must admit. When I first started growing parsnips (Petroselinum hortense), I wasn’t impressed. They seemed to take forever to germinate, they grew slowly, and the carrot-shaped roots looked fine but didn’t have any special flavor. Then I learned to let them get exposed to the cold and even overwinter in the garden then pick. The difference in flavor made it all worth while. These white roots turned sweet and flavorful making perfect additions to roasted root crop casseroles, mashed, or tossed in soups and stews.

Parsnip roots on table

Although they’re widely grown in England and Europe, American gardeners have been slow to warm up to parsnips. I grow them because they fit in my, “plant it and forget about it” category of vegetables. Once growing they require little work and reward you with sweet roots in fall and winter.

When to Plant

Like carrots, sow parsnip seeds 2 weeks before your last frost date in your area. That would be April or May.

Where to Plant

Parsnips grow best in full sun, but can take only 3 to 4 hours of direct sun and still produce a crop. They do, however, need a well-drained loose soil, so grow them in a bed raised 8 inches off the ground, 3 feet wide and as long as you like. Plant so these roots don’t get shaded by other crops during the summer.

How to Plant

Amend the raised bed with compost before planting. Remove rocks and debris from the bed that may block the growth of the roots. Sow the flat seeds 1/2 inch deep, 1/2 inch apart in rows spaced 18 inches apart. The seeds are large enough to easily space them properly. Parsnips do take up to 3 weeks to germinate, so I like to cover the seeds with sand or potting soil, water, and then lay a floating row cover over the bed to keep it moist. Once the seeds germinate, remove the row cover. Another method I’ve used is to poke 6 inch deep holes in the soil with a trowel handle, fill the hole with potting soil and plant seed 1/2 inch deep. This way the parsnip roots are able to grow straight and long into the potting soil.

Care and Maintenance

Once the seeds germinate, thin so there is at least 4 inches between plants. Parsnips need room to expand, so if they aren’t properly thinned, you’ll get thin and spindly roots. Because they take so long to germinate, it’s important to keep your parsnip bed weeded well early in the season. Keep the bed well watered. Water deeply so it soaks at least 6 inches into the soil. Mulch between the parsnip rows with straw to help keep the soil moist and weed free.

Parsnips have few pests. A floating row cover kept on young plants will help ward off leafhoppers and rabbits from feeding on your seedlings.

Harvest

As I mentioned, don’t rush to harvest parsnip roots. They taste best after a month of cool temperatures in fall. I’ve even had success mulching them with a 6 inch thick layer of hay in November and leaving the roots to overwinter in the soil. In March or April, once the ground thaws, but before the roots sprout new shoots, dig up the parsnips and cook them. You’ll be amazed at how sweet they taste.

Additional Information

They aren’t many varieties of parsnips, but here are the ones I’ve found produce well. ‘Lancer’ and ‘Javelin Hybrid’ germinate well, and produce clean, white, smooth roots about 100 days after seeding.

Text excepted from the Northeast Vegetable and Fruit Gardening book.

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