If you live in a climate with harsh winters, starting your parsnips indoors and then transplanting will greatly improve your chances of successful parsnip growth in time for a late fall harvest. Follow these tips below to germinate and transplant your parsnips with a high percentage of success.
Start Seeds Early
Prepare parsnip seeds for germination about 4 weeks before you want to transplant them outdoors to the garden. Set up a potting station with a large tray, several cardboard tubes, like those from bathroom tissue, and commercial garden potting soil. Use potting soil that has no peat moss as parsnips prefer a low pH growth medium. Put a few seeds into each cardboard tube then plant these just below the level of the soil in the tray. Water well upon planting, and keep the soil moist throughout the germination period.
Thin Out the Seedlings
From 4 to 6 weeks later you will have several dozen seedlings in your tray. Thin out the seedlings so only the strongest one remains in each cardboard tube.
Test the Soil for Transplanting
Perform a pH test on the soil where you want to plant the parsnips. If it is too acid, bring up the alkalinity of the soil with powdered lime. If it is too alkaline, with a pH above 7, add some peat moss or dried manure to the soil. Also check for the moisture retention of the soil. Add coarse sand instead of pebbles or stones to improve drainage. Dig out all the rocks and stones from the soil that you can find. The parsnips will divide and fork around the rocks in the soil. Parsnips will also fork in the presence of too much nitrogen.
Check the Soil Temperature
As soon as the soil temperature has risen above freezing, scrape off the top layer of garden soil and get the seedlings in. They benefit from cold weather at the start and the ending of the growing season.
Scrape two or more rows in the soil, and plant the parsnip seedlings about 1/2 inch down in the dirt. Plant them well apart, with 6 to 8 inches between seedlings. Shake soil through a sifter over the roots and stems of the seedlings and tamp down the dirt solidly over the root crowns. Leave the seedlings in the cardboard tubes as this will help train the roots to expand at the top for the first few inches, reducing the likelihood that they will branch or fork later.
Water the Seedlings Well
Water the soil around the seedlings well and keep it damp to the touch during the growing season. This moisture helps the parsnip roots develop a healthy texture and water content, and enhances the sweet taste of this vegetable.
The seedlings will take another 2 weeks to 30 days to firmly settle in the garden, during which time unchecked weeds will steal all their water and nutrients. Pull up the weeds without using any garden tools as much as possible.
Fertilize at Transplant and 3 Months Later
Use a root-developing fertilizer to help the parsnips resist forking. Boost soil nutrition with a side feed of this same fertilizer in midsummer.