When to Plant Parsnip in Napa County, CA
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.
Napa County, California is in USDA Zone 9a. The average last spring frost is February 26 and the first fall frost is November 26, giving you a growing season of approximately 273 days.
At an elevation of 449 feet, Napa County receives approximately 35 inches of rainfall annually with predominantly loam soil. Summer highs average 88°F, providing good warmth for Parsnip during the growing season.
Napa County Soil Profile
Soil Type
Loam
Soil pH
6.7-7.5
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
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Parsnip Planting Timeline — Napa County, CA
Parsnip Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Direct Sow | February 5 | Feb 5 – Feb 26 |
| Fall Sowing | October 1 | Oct 1 – Oct 15 |
| Harvest | May 21 | May 21 – Jul 2 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Direct Sow |
| March | — |
| April | — |
| May | Harvest |
| June | Harvest |
| July | Harvest |
| August | — |
| September | — |
| October | Fall Sowing |
| 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 9a
Growing Season
273 days
Growing Tips for Napa 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 Napa County, CA?
Napa County is in Zone 9a with an average last frost of February 26. Plan your Parsnip planting based on this frost date — see the calendar above for exact timing.
What planting zone is Napa County, CA?
Napa County, California is in USDA Hardiness Zone 9a. The average last spring frost is February 26 and first fall frost is November 26.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Napa County gardeners in Zone 9a organize planting dates, track what's growing, and never miss a planting window.
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