When to Plant Celeriac in Knox County, TX
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.
Knox County, Texas is in USDA Zone 7b. The average last spring frost is March 24 and the first fall frost is November 12, giving you a growing season of approximately 233 days.
At an elevation of 1,847 feet, Knox County receives approximately 51.2 inches of rainfall annually with predominantly loam soil. Summer highs average 93°F, providing good warmth for Celeriac during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Celeriac root diseases.
Knox County Soil Profile
Soil Type
Loam
Soil pH
6.4-7.2
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 Knox County
How your county's soil matches Celeriac's growing requirements.
Soil pH
Your soil pH (6.4–7.2) overlaps with Celeriac's range (6.0–7.0), though not a perfect match.
Soil Texture
The loam soil in Knox County is excellent for Celeriac — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is low (1.9%). Add 2-3 inches of compost before planting Celeriac.
How to Plant Celeriac
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Plant Water Budget
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 | — | 1.3" | 0" | ❄️ Dormant |
| Feb | — | 2.1" | 0" | ❄️ Dormant |
| Mar | 3.9" | 3.2" | 0.7" | 💧 Light watering |
| Apr | 3.9" | 6.4" | 0" | ✅ Rainfall sufficient |
| May | 3.9" | 6.7" | 0" | ✅ Rainfall sufficient |
| Jun | 3.9" | 7.3" | 0" | ✅ Rainfall sufficient |
| Jul | 3.9" | 6.5" | 0" | ✅ Rainfall sufficient |
| Aug | 3.9" | 5.9" | 0" | ✅ Rainfall sufficient |
| Sep | 3.9" | 5.4" | 0" | ✅ Rainfall sufficient |
| Oct | 3.9" | 3.3" | 0.6" | 💧 Light watering |
| Nov | 3.9" | 1.8" | 2.1" | 🚿 Regular watering |
| Dec | — | 1.3" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Mar–Nov in Knox 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 — Knox County, TX
Celeriac Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 17 | Feb 17 – Mar 3 |
| Transplant Outdoors | March 24 | Mar 24 – Apr 7 |
| Direct Sow | March 10 | Mar 10 – Mar 31 |
| Harvest | July 7 | Jul 7 – Aug 11 |
| Fall Sowing | September 3 | Sep 3 – Sep 17 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | Start Indoors Transplant Outdoors Direct Sow |
| April | Transplant Outdoors |
| May | — |
| June | — |
| July | Harvest |
| August | Harvest |
| September | Fall Sowing |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.9"/week · Natural rainfall sufficient
📅 Days to Maturity
100–120 days
🧪 Soil pH
Needs 6–7 · Your soil: acceptable
🗺️ USDA Zone
Zone 7b
📆 Growing Season
233 days in Knox County
Growing Tips for Celeriac in Knox County
Direct sow Celeriac outdoors after March 24 in Knox County when soil has warmed and frost danger has passed.
Common pests for Celeriac 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. Remove side roots as they develop to encourage a single large bulb. Harvest after a light frost for best flavor.
Companion Planting
Good Companions
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Celeriac in Other Locations
Frequently Asked Questions
When should I plant Celeriac in Knox County, TX?
Knox County is in Zone 7b with an average last frost of March 24. Plan your Celeriac planting based on this frost date — see the calendar above for exact timing.
What planting zone is Knox County, TX?
Knox County, Texas is in USDA Hardiness Zone 7b. The average last spring frost is March 24 and first fall frost is November 12.
Plan Your Garden with Confidence
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