When to Plant Celery in Washington County, IA
Celery is a marshland plant that requires consistent moisture and cool temperatures to produce crisp, flavorful stalks. It is a rewarding but demanding garden crop.
Washington County, Iowa is in USDA Zone 5a. The average last spring frost is April 21 and the first fall frost is October 14, giving you a growing season of approximately 176 days.
At an elevation of 542 feet, Washington County receives approximately 30.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 83°F, so choose short-season varieties of Celery to ensure they mature before fall.
Washington County Soil Profile
Soil Type
Silt Loam
Soil pH
5.9-6.7
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
Celery Planting Timeline — Washington County, IA
Celery Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 17 | Mar 17 – Mar 31 |
| Transplant Outdoors | April 21 | Apr 21 – May 5 |
| Direct Sow | April 7 | Apr 7 – Apr 28 |
| Fall Sowing | August 5 | Aug 5 – Aug 19 |
| Harvest | July 14 | Jul 14 – Sep 8 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Transplant Outdoors Direct Sow |
| May | Transplant Outdoors |
| June | — |
| July | Harvest |
| August | Fall Sowing Harvest |
| September | Harvest |
| October | — |
| November | — |
| December | — |
Growing Conditions
Sun
Full Sun (6-8+ hours)
Water
High — keep soil consistently moist
Days to Maturity
80–120 days
Soil pH
6 – 7
USDA Zone
Zone 5a
Growing Season
176 days
Growing Tips for Washington County
Start seeds indoors 10-12 weeks before last frost. Keep soil consistently moist and never let it dry out. Blanch stalks by mounding soil or using collars for milder flavor.
Companion Planting
Good Companions
Avoid Planting Near
Level Up Your Garden
Celery in Other Locations
Frequently Asked Questions
When should I plant Celery in Washington County, IA?
Washington County is in Zone 5a with an average last frost of April 21. Plan your Celery planting based on this frost date — see the calendar above for exact timing.
What planting zone is Washington County, IA?
Washington County, Iowa is in USDA Hardiness Zone 5a. The average last spring frost is April 21 and first fall frost is October 14.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Washington County gardeners in Zone 5a organize planting dates, track what's growing, and never miss a planting window.
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