When to Plant Celery in Washington County, WI
Your August game plan for Washington County, Wisconsin
If you only do a handful of things in the garden this August, make it these. They're sequenced around your zone's frost timing.
-
Harvest celery as they ripen
Taste as you pick. The first ripe produce is the best feedback loop you'll get all season.
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Sow celery for an autumn harvest
Your first frost is about 8 weeks away — plenty of time for these to mature.
September prep starts now
- First harvests: celery
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, Wisconsin is in USDA Zone 5b. The average last spring frost is April 27 and the first fall frost is October 11, giving you a growing season of approximately 167 days.
At an elevation of 1,141 feet, Washington County receives approximately 33.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85°F, providing good warmth for Celery during the growing season.
Washington County Soil Profile
Soil Type
Silt Loam
Soil pH
6.1-6.7
Drainage
Well Drained
Celery 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.
Soil Compatibility in Washington County
How your county's soil matches Celery's growing requirements.
Soil pH
Your soil pH (6.1–6.7) is within Celery's preferred range (6.0–7.0).
Soil Texture
The silt loam soil in Washington County is excellent for Celery — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (4.3%) — Celery will thrive.
How to Plant Celery
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Succession Planting Celery
Sow every 9.1 weeks. Last sowing by Jun 13 to harvest before frost.
For a dedicated fall crop, sow by Aug 02.
Celery Water Budget
Monthly Watering Guide for Celery
Celery needs approximately 1.3 inches of water per week (5.6" per month). Here's how your county's rainfall compares month by month.
| Month | Celery Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.5" | 0" | ❄️ Dormant |
| Feb | — | 1.4" | 0" | ❄️ Dormant |
| Mar | — | 2.3" | 0" | ❄️ Dormant |
| Apr | 5.6" | 3.5" | 2.1" | 💧 Light watering |
| May | 5.6" | 3.5" | 2.1" | 💧 Light watering |
| Jun | 5.6" | 4.2" | 1.4" | 💧 Light watering |
| Jul | 5.6" | 3.3" | 2.3" | 💧 Light watering |
| Aug | 5.6" | 4" | 1.6" | 💧 Light watering |
| Sep | 5.6" | 2.8" | 2.8" | 🚿 Regular watering |
| Oct | 5.6" | 3" | 2.6" | 💧 Light watering |
| Nov | — | 2.2" | 0" | ❄️ Dormant |
| Dec | — | 2.1" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Washington County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Celery Heat Requirements (GDD)
What are Growing Degree Days (GDD)?
Growing Degree Days measure the total warmth your plants receive during the growing season. Think of it as a "heat bank" — every day above 50°F deposits warmth that helps your plants grow.
Each plant needs a certain amount of accumulated heat to mature. If your county provides more GDD than the plant needs, it's a great fit. If it's close, you may want to choose faster-maturing varieties or start seeds indoors to get a head start.
Celery Planting Timeline — Washington County, WI
Celery Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 23 | Mar 23 – Apr 6 |
| Transplant Outdoors | April 27 | Apr 27 – May 11 |
| Direct Sow | April 13 | Apr 13 – May 4 |
| Harvest | July 20 | Jul 20 – Sep 14 |
| Fall Sowing | August 2 | Aug 2 – Aug 16 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Start Indoors Transplant Outdoors Direct Sow |
| May | Transplant Outdoors Direct Sow |
| June | — |
| July | Harvest |
| August | Fall Sowing Harvest |
| September | Harvest |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1.3"/week · 1-2 times/week
📅 Days to Maturity
80–120 days
🧪 Soil pH
Needs 6–7 · Your soil: ideal
🗺️ USDA Zone
Zone 5b
📆 Growing Season
167 days in Washington County
Growing Tips for Celery in Washington County
Direct sow Celery outdoors after April 27 in Washington County when soil has warmed and frost danger has passed.
Common pests for Celery in this region include carrot rust fly and parsleyworm. Use row covers early in the season and inspect plants weekly.
General growing tips
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
Check more plant combinations with our Companion Planting Checker →
Celery in Other Locations
Frequently Asked Questions
When should I plant Celery in Washington County, WI?
Washington County is in Zone 5b with an average last frost of April 27. Plan your Celery planting based on this frost date — see the calendar above for exact timing.
What planting zone is Washington County, WI?
Washington County, Wisconsin is in USDA Hardiness Zone 5b. The average last spring frost is April 27 and first fall frost is October 11.
Your Washington County Garden Planner — Free
A 22-page printable planner built for Washington County (Zone 5b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.