When to Plant Celeriac in Madera County, CA
Your May planting checklist for Madera County, California
Here's what deserves your attention in Madera County, California this month. Everything below is tailored to Zone 9a and timed around your local frost dates.
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Get celeriac seeds going inside
These need a head start before your last frost (April 18). Sow into cells now so you're ready to transplant in a few weeks.
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.
Madera County, California is in USDA Zone 9a. The average last spring frost is April 18 and the first fall frost is November 9, giving you a growing season of approximately 205 days.
At an elevation of 187 feet, Madera County receives approximately 14.5 inches of rainfall annually with predominantly loam soil. Summer highs average 104°F, so Celeriac may need afternoon shade and extra watering during peak heat. With low rainfall, drip irrigation is essential for growing Celeriac successfully. Mulch heavily to conserve soil moisture.
Madera County Soil Profile
Soil Type
Loam
Soil pH
6.2-7.8
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.
Soil Compatibility in Madera County
How your county's soil matches Celeriac's growing requirements.
Soil pH
Your soil pH (6.2–7.8) overlaps with Celeriac's range (6.0–7.0), though not a perfect match.
Soil Texture
The loam soil in Madera County is excellent for Celeriac — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.6%). Annual compost additions will help Celeriac.
How to Plant Celeriac
Fall planting: Sow 8 weeks before your first frost date for a fall harvest.
Plant Water Budget
Water stress score is 8/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Celeriac
Celeriac needs approximately 0.9 inches of water per week (3.9" per month). Here's how your county's rainfall compares month by month.
| Month | Celeriac Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 2.6" | 0" | ❄️ Dormant |
| Feb | — | 2.9" | 0" | ❄️ Dormant |
| Mar | — | 2.3" | 0" | ❄️ Dormant |
| Apr | 3.9" | 1.3" | 2.6" | 🚿 Regular watering |
| May | 3.9" | 0.4" | 3.5" | 🚿 Regular watering |
| Jun | 3.9" | 0.1" | 3.8" | 🚿 Regular watering |
| Jul | 3.9" | 0" | 3.9" | 🚿 Regular watering |
| Aug | 3.9" | 0" | 3.9" | 🚿 Regular watering |
| Sep | 3.9" | 0.1" | 3.8" | 🚿 Regular watering |
| Oct | 3.9" | 0.7" | 3.2" | 🚿 Regular watering |
| Nov | 3.9" | 1.4" | 2.5" | 🚿 Regular watering |
| Dec | — | 2.7" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Nov in Madera County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Celeriac 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.
Celeriac Planting Timeline — Madera County, CA
Celeriac Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 21 | Mar 21 – Apr 4 |
| Transplant Outdoors | April 18 | Apr 18 – May 2 |
| Direct Sow | March 28 | Mar 28 – Apr 18 |
| Harvest | August 1 | Aug 1 – Sep 5 |
| Fall Sowing | September 14 | Sep 14 – Sep 28 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors Direct Sow |
| April | Start Indoors Transplant Outdoors Direct Sow |
| May | Transplant Outdoors |
| June | — |
| July | — |
| August | Harvest |
| September | Fall Sowing Harvest |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.9"/week · 2-3 times/week
📅 Days to Maturity
100–120 days
🧪 Soil pH
Needs 6–7 · Your soil: acceptable
🗺️ USDA Zone
Zone 9a
📆 Growing Season
205 days in Madera County
Growing Tips for Celeriac in Madera County
Direct sow Celeriac outdoors after April 18 in Madera County when soil has warmed and frost danger has passed.
With summer highs reaching 104°F in Madera County, provide afternoon shade for Celeriac and water deeply in the morning.
Common pests for Celeriac in this region include carrot rust fly and parsleyworm. Use row covers early in the season and inspect plants weekly.
Madera County receives only 14" of rain annually. Celeriac needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.
General growing tips
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 Madera County, CA?
Madera County is in Zone 9a with an average last frost of April 18. Plan your Celeriac planting based on this frost date — see the calendar above for exact timing.
What planting zone is Madera County, CA?
Madera County, California is in USDA Hardiness Zone 9a. The average last spring frost is April 18 and first fall frost is November 9.
Your Madera County Garden Planner — Free
A 24-page printable planner built for Madera County (Zone 9a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.