When to Plant Parsnip in Jefferson County, MO
Parsnips are a sweet, nutty root vegetable that develops best flavor after exposure to frost. They require a long growing season but reward patient gardeners.
Jefferson County, Missouri is in USDA Zone 6b. The average last spring frost is April 10 and the first fall frost is October 26, giving you a growing season of approximately 199 days.
At an elevation of 839 feet, Jefferson County receives approximately 33.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 87°F, providing good warmth for Parsnip during the growing season.
Jefferson County Soil Profile
Soil Type
Silt Loam
Soil pH
5.7-7.1
Drainage
Well Drained
Plant Planting Risk Windows
Percentages indicate frost risk at transplant. The 70% safe window means there is a 30% chance of frost after transplant — suitable for cold-hardy crops or gardeners with frost protection. The 90% safe window is best for tender plants.
Plant Water Budget
Parsnip Planting Timeline — Jefferson County, MO
Parsnip Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Direct Sow | March 27 | Mar 27 – Apr 17 |
| Fall Sowing | August 17 | Aug 17 – Aug 31 |
| Harvest | July 10 | Jul 10 – Aug 21 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Direct Sow |
| April | Direct Sow |
| May | — |
| June | — |
| July | Harvest |
| August | Fall Sowing Harvest |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
Sun
Full Sun (6-8+ hours)
Water
Moderate — regular watering
Days to Maturity
100–130 days
Soil pH
6 – 7
USDA Zone
Zone 6b
Growing Season
199 days
Growing Tips for Jefferson County
Use only fresh seed as parsnip seed viability declines rapidly. Sow directly in spring in deeply worked soil. Leave roots in the ground through winter for sweetest flavor.
Companion Planting
Good Companions
Avoid Planting Near
Level Up Your Garden
Parsnip in Other Locations
Frequently Asked Questions
When should I plant Parsnip in Jefferson County, MO?
Jefferson County is in Zone 6b with an average last frost of April 10. Plan your Parsnip planting based on this frost date — see the calendar above for exact timing.
What planting zone is Jefferson County, MO?
Jefferson County, Missouri is in USDA Hardiness Zone 6b. The average last spring frost is April 10 and first fall frost is October 26.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Jefferson County gardeners in Zone 6b organize planting dates, track what's growing, and never miss a planting window.
Get Your Free Garden Planner →Free download. Plan your entire garden season in minutes.