When to plant Celeriac in Madison County, ID
Aim to plant Celeriac in Madison County on or after May 17; the window stays open through June 7. Madison County's 103-day frost-free season gives you just enough for one full spring planting. A second sowing from July 3 to July 17 extends the harvest into fall.
When to Plant Celeriac in Madison County, ID
Celeriac is a celery relative grown for its knobby, flavorful root rather than its stalks. It has a rich celery flavor and is excellent roasted, mashed, or in soups.
Madison County, Idaho is in USDA Zone 5a. The average last spring frost is May 31 and the first fall frost is September 11, giving you a growing season of approximately 103 days.
At an elevation of 6,385 feet, Madison County receives approximately 19 inches of rainfall annually with predominantly loam soil. Summer highs average 85°F, providing good warmth for Celeriac during the growing season. With low rainfall, drip irrigation is essential for growing Celeriac successfully. Mulch heavily to conserve soil moisture.
Madison County Soil Profile
Soil Type
Loam
Soil pH
6.2-7.8
Drainage
Well Drained
Monthly Watering Guide for Celeriac
Celeriac needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Celeriac Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.1" | 0" | ❄️ Dormant |
| Feb | — | 1" | 0" | ❄️ Dormant |
| Mar | — | 1.9" | 0" | ❄️ Dormant |
| Apr | — | 2.1" | 0" | ❄️ Dormant |
| May | 4.3" | 2.5" | 1.8" | 💧 Light watering |
| Jun | 4.3" | 1.2" | 3.1" | 🚿 Regular watering |
| Jul | 4.3" | 1.6" | 2.7" | 🚿 Regular watering |
| Aug | 4.3" | 2.2" | 2.1" | 💧 Light watering |
| Sep | 4.3" | 1.6" | 2.7" | 🚿 Regular watering |
| Oct | — | 1.6" | 0" | ❄️ Dormant |
| Nov | — | 1.3" | 0" | ❄️ Dormant |
| Dec | — | 1" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Sep in Madison County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Celeriac Planting Timeline — Madison County, ID
Celeriac Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | April 26 | Apr 26 – May 10 |
| Transplant Outdoors | May 31 | May 31 – Jun 14 |
| Direct Sow | May 17 | May 17 – Jun 7 |
| Harvest | September 13 | Sep 13 – Oct 18 |
| Fall Sowing | July 3 | Jul 3 – Jul 17 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Start Indoors |
| May | Start Indoors Transplant Outdoors Direct Sow |
| June | Transplant Outdoors Direct Sow |
| July | Fall Sowing |
| August | — |
| September | Harvest |
| October | Harvest |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
High — keep soil consistently moist
📅 Days to Maturity
100–120 days
🧪 Soil pH
Needs 6–7 · Your soil: N/A
🗺️ USDA Zone
Zone 5a
📆 Growing Season
103 days in Madison County
Growing Tips for Madison County
Start seeds indoors 10-12 weeks before last frost. Remove side roots as they develop to encourage a single large bulb. Harvest after a light frost for best flavor.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Celeriac in Other Locations
Frequently Asked Questions
When should I plant Celeriac in Madison County, ID?
Madison County is in Zone 5a with an average last frost of May 31. Plan your Celeriac planting based on this frost date — see the calendar above for exact timing.
What planting zone is Madison County, ID?
Madison County, Idaho is in USDA Hardiness Zone 5a. The average last spring frost is May 31 and first fall frost is September 11.
When should I plant Celeriac in Madison County, ID?
In Madison County, ID, plant Celeriac after the last frost (around May 31) and before the first frost (around September 11). Best results when soil holds above 50°F.
What growing zone is Madison County, ID for Celeriac?
Madison County sits in USDA Zone 5a. Celeriac grows reliably in zones 3a through 9b, so it's a good fit here.
Can Celeriac grow in Madison County's climate?
Yes — Celeriac grows well in Madison County's temperate climate. Madison County averages a 103-day frost-free season, with last frost around May 31 and first frost around September 11.
Your Madison County Garden Planner — Free
A 22-page printable planner built for Madison County (Zone 5a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.