How to Grow Parsnips in Your Home Garden

Parsnips make an excellent crop for a home garden.

1. 1. Season: In most climates, parsnips should go in the ground in early spring, typically the first or second week of April, when soil temperatures average 50ºF or higher. Persistently cold soil can produce seed rot, so don't start parsnips in the ground too soon.
2. 2. Soil: Parsnips do best in deep, loamy soil with a neutral to mildly acidic soil pH. They can also tolerate sandy soils, but heavy clay or rocky soils will result in misshapen parsnips. If your soil is low in organic matter, mix in a layer of compost.
3. 3. Planting: Sow fresh seeds directly into the soil, about half an inch deep and spaced half an inch apart.
4. 4. Thinning: Depending on the germination rate of your seeds, you may have more seedlings than your garden can accommodate. Once they’ve sprouted, thin parsnip seedlings so they’re spaced six inches apart.

Parsnip seeds may take upwards of a month to germinate, and the species has a long growing season—roughly 100 days from planting to harvest.

1. 1. Watering: Parsnip roots push deep into the soil, so you'll want to water them with thorough soakings when the soil dries out. Drip irrigation is the most efficient way to soak the soil. Place a thin layer of mulch atop the soil to help it retain moisture.
2. 2. Pests: Most parsnip varieties can withstand pestilence, but you should still be on the lookout for pests. Swallowtail caterpillars eat parsnip leaves; handpick them off when they appear. Aphids also eat parsnip stems and leaves; wash them away with water. Parsnip roots can fall prey to carrot fly maggots, so counteract this by planting parsnips alongside companion plants like chives, which repel maggots.
3. 3. Root rot: Parsnip canker affects parsnip crowns and can contribute to root rot. Parsnips that have been damaged by carrot rust fly larvae are more susceptible to parsnip canker, so be extra careful to eliminate pets. When growing parsnips, make sure to clear away pieces of last season’s parsnips (and other vegetables in the carrot family) that may still be in the soil, as they can harbor parsnip canker spores. Lastly, cover the tops of parsnips with soil to make them less susceptible to fungus.

Avoid transplanting parsnips if at all possible. Let them thrive in your vegetable garden by regularly watering them and weeding the area surrounding them.

When parsnip leaves begin to die back, your crop is ready for harvest. You can harvest parsnips in the summer or fall, but mature plants can actually handle freezing temperatures. If you wait to harvest parsnips until after a hard frost, they are likely to come out sweeter than a crop picked early in the season.

Parsnips are biennial plants, which means they produce flowers every other year. With flowers come seeds, so by the second year of your plants’ life, you'll have fresh seeds you can use to grow more. Parsnips preserve well, too, so they can serve as a standby ingredient for winter vegetable stews and roasts.

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