When to Harvest Parsnips
Why parsnips are a fall crop, and how cold makes them sweeter.
When to harvest parsnips is in fall, ideally after a light frost. The University of Minnesota says to harvest when the roots reach the size you want and/or after a light frost.
Cold is what sweetens them. The University of Massachusetts explains that starches in parsnip roots convert to sugar at cold temperatures, and that parsnips dug early in fall can be sweetened with two to three weeks of cold storage.
Parsnip harvest at a glance: Dig parsnips in fall, after a light frost, and before the ground freezes hard. Dug early? Two to three weeks of cold storage near 0°C sweetens them. Remove the tops and store cold and moist; they keep for about four months.
Harvesting carrots too? See When to Harvest Carrots for the same fall timing.
After Frost, Before Freeze-Up
Parsnips are slow, so they are usually the last crop out. Dig after the first light frost and before the soil freezes too hard to dig:
| City | Zone | Average First Fall Frost |
|---|---|---|
| Vancouver | 8b | Nov 30 |
| Kelowna | 6b | Oct 15 |
| Calgary | 3b | Sep 21 |
| Edmonton | 4a | Sep 23 |
| Saskatoon | 3a | Sep 12 |
| Winnipeg | 3a | Sep 20 |
| Thunder Bay | 3b | Sep 20 |
| Ottawa | 5a | Oct 12 |
| Toronto | 6b | Nov 1 |
| Montréal | 5b | Oct 7 |
| Quebec City | 5a | Sep 28 |
| Fredericton | 5a | Sep 26 |
| Halifax | 6a | Oct 18 |
| St. John’s | 5b | Oct 13 |
Frost dates from this site’s data.
Digging
Parsnips have long roots. Loosen the soil alongside the row with a fork before lifting so the roots do not snap.
Storing Parsnips
The University of Massachusetts gives the ideal as 0°C (32°F) and 90–95% humidity with greens removed, for 2 to 6 months. The University of Minnesota says to store them cold and moist, not to let them freeze, and expects about four months; it notes parsnips sweeten after two weeks at 0°C. Keep them away from apples and pears, which the University of Massachusetts says cause bitterness through ethylene.
Leaving Parsnips in Over Winter
The University of Saskatchewan reports that some Prairie gardeners overwinter parsnips in the ground and dig them in spring. Its advice: in late fall, just before the ground freezes, cover the row with at least 15 cm of straw or leaves (hold leaves down with burlap pinned at the edges), then pull the mulch back in spring and harvest.
It also notes parsnips need about 130 days or more from seeding and can be hard to grow in the northern Prairies, where the frost-free season is short.
Frequently Asked Questions
When should I harvest parsnips?
In fall, after a light frost and before the ground freezes hard. The University of Minnesota says to harvest when roots reach the size you want and/or after a light frost.
Why are parsnips sweeter after frost?
Cold converts starch in the roots to sugar, according to the University of Massachusetts.
Can I sweeten parsnips dug before frost?
Yes. The University of Massachusetts says two to three weeks of cold storage sweetens early-dug parsnips.
How do I store parsnips?
Cold and moist, near 0°C, with the tops removed and away from apples and pears.
How long do parsnips keep?
About four months according to the University of Minnesota, and 2 to 6 months in ideal conditions according to the University of Massachusetts.
How do I dig parsnips without breaking them?
Loosen the soil alongside the row with a fork first, then lift. Parsnip roots are long and snap easily.
Sources
- University of Minnesota Extension — Harvesting and storing home garden vegetables
- University of Massachusetts Amherst Extension — Optimal Storage Conditions and Ethylene Sensitivity of Fall Storage Crops
- Environment and Climate Change Canada — Canadian Climate Normals (the frost dates in the tables, read from this site’s frost data)
- University of Saskatchewan, Gardening at USask — Parsnips