About Growing Parsnips
Pastinaca sativa
Parsnips look like large, creamy-white carrots, even though they’ve never gained the same kind of popularity. But gardeners are now discovering the delicious benefits of growing and cooking with parsnips. The roots become sweeter when left in the ground until after the first frost. They’re also versatile and can be boiled and mashed like potatoes or baked, steamed or sautéed.
How to Grow Parsnips
Parsnips are a long-season crop, taking at least 100 days to mature. They grow well in Colorado because freezing improves flavor. Parsnips are considered a semi-hardy, cool-season crop because they grow best when daytime temperatures range from 40 to 50 degrees.
Prepare
- Parsnips prefer a light, rich soil. Wait until the vegetable garden is dry enough to work in spring and then dig deeply and amend the planting area with a good amount of compost or other organic matter.
- Parsnips need a loose, aerated soil to grow into well-shaped roots. If the soil is too dense, or there are rocks, tree roots or other debris, the parsnips can grow into odd or crooked shapes.
Plant
- Plant parsnip seeds in early spring, at least two weeks before the last average frost date or when soil temperatures are close to 50 degrees. Soak seeds overnight before planting and allow several weeks for them to germinate.
- Plant seeds ½ inch deep and thickly in a row. Space rows at least 18 inches apart. Some gardeners mix radish seeds in with their parsnip seeds. Because the radishes will germinate quickly, they help mark the parsnip rows and keep the top of the soil from crusting.
- Mulch lightly to keep the soil cool and moist, and to eliminate weeds. Don’t let the soil or seeds dry out.
Maintain
- After the seedlings emerge, thin the plants to 3 to 4 inches apart in each row. The closer the plants grow together, the smaller and more tender the roots will be.
- Sidedress plants with a well-balanced fertilizer at the 4-5 week mark by sprinkling a dry, well-balanced fertilizer on the sides of the rows, but away from the plants. Rake in and keep up with watering.
- Pull or snip weeds as they show up so they won’t compete with the parsnip roots.
Harvest
- To harvest, wait until temperatures fall below 35 degrees to allow the starch to convert to sugar. Then dig – don’t pull – the roots. Parsnip roots grow quite long and they need to be dug with a garden fork or shovel.
- If you want to enjoy your parsnip crop for a longer period of time, cover some with a layer of leaves and dig them through the winter when the soil thaws. Start digging again in early spring before the tops begin to regrow.
Companion Plants
Plant parsnips with these companions:
- Endive
- Escarole
- Lettuce
- Onions
- Radishes
Materials for Success
- Soil thermometer
- Soaker hose
- High-quality compost and manure
- Light-weight mulch
- Radish seeds
- Well-balanced fertilizer
- Garden fork
To learn more about growing parsnips or about growing your own edible vegetable garden, contact the pros at Nick’s Garden Center.