http://www.durgan.org/URL/?ASIVP 12 April 2011 All American Parsnips
Parsnip seed was sowed at 2 inch spacing, which will be thinned to about four inches after growth commences. The seed was covered with a board to improve germination. The board keeps seed cool from direct sun, maintains moisture, and stops dispersal when rain falls. Parsnip germinate at cool temperatures, and is placed in the ground as soon as the ground is ready in the Spring.
Almost every seed germinated using the above described method, and thinning was commenced to four inches when he seedlings were large enough. Parsnip seed can be difficult to germinate, and seed should be from last years plants to insure freshness. Sometimes the parsnips get quite large. They have a long tap root and need little care after germination. They store well in a cold room (similar to storing potatoes) and make a good substitute for potatoes.