The parsnip, a root vegetable, had a long history as a nutritious starch tuber before the introduction of the potato from the New World. It is easy to grow from seeds, but can also be propagated from cuttings. A biennial plant, a parsnip will grow leaves and flowers in its first year, and produce its long firm white roots in the second year. Learn more about methods for propagating parsnip from these suggestions.
Where to Grow Parsnips
Parsnips grow best in a soil that is slightly alkaline, so test the soil pH in the spot where you want to grow them about 6 weeks prior to planting seeds. Ensure the soil is well-tilled and smooth, as stony soil will cause the parsnips to "fork", that is, to divide into multiple small pointed roots instead of one large root mass. Add sand to the soil to promote drainage if needed. Plant parsnips in full sun to light shade between rows of radishes or lettuce.
When to Plant Parsnips
Parsnips take most of the growing season to mature, and, in fact, should not be harvested before a deep frost. Plant the seeds early in the spring as soon as frost has lifted. Use fresh seeds as parsnip seeds do not retain their fertility in storage.
How to Plant Parsnips
Dig and break up the soil finely in rows 12 to 18 inches apart, and 3/4 inch deep. Plant parsnip seeds 1 inch apart. Do your planting on a calm day, as parsnip seeds are very light and can blow away in a strong breeze. Sift some soil in a strainer over the seeds, and pack the soil down firmly. Water the plantings at once and continue to water weekly.
Growing Parsnips from Cuttings
Take a cutting from a strong root and plant it in the late fall. It will overwinter well and will produce new parsnips in the next growing season. Avoid fertilizing with a high-nitrogen fertilizer as this will cause the parsnip roots to fork. Use a root-promoting blend with more phosphorus than nitrogen.
Growing Parsnips from Pre-Germination
Use a large planting tray with commercial potting soil. Plant 3 to 5 parsnip seeds each in small cardboard rolls as used for bathroom tissue. The cardboard roll helps prevent branching of the new roots. Water them often to keep the soil surface damp. Plant outdoors once the leafy stems reach 2 to 4 inches in height, and continue to water well to enhance the texture and flavor of the parsnip roots.
Care of Parsnips
Water well, especially in hot weather. Keep weeds pulled, and pull the weeds gently with a rake instead of cutting with a hoe to avoid damaging the parsnip roots. Canker development can result from accidentally cutting into the outer root area. Fertilize with low-nitrogen fertilizer once a month.
Leave parsnips in the ground until a first frost. Parsnip roots take all season to reach their maximum length of 20 inches. You can store parsnips for a few weeks in a light bed of sand kept at 32 degrees F. (0 C.) after harvesting.