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When to Plant Celeriac in Polk County, TX

Polk County, Texas Zone 9a May

This month in Polk County, Texas

May rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in Polk County, Texas.

Avg. last frost March 4
Avg. first frost November 23
Soil temp (4") 72°F
Watering Low
Pest pressure High
Daylight 13.6 hrs
Looking ahead to June
  • First harvests: celeriac

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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.

Polk County, Texas is in USDA Zone 9a. The average last spring frost is March 4 and the first fall frost is November 23, giving you a growing season of approximately 264 days.

At an elevation of 292 feet, Polk County receives approximately 63 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 96°F, so Celeriac may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring — great for early planting — but Celeriac will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Celeriac root diseases.

Polk County, TX (Zone 9a) Long season
264 days
Last Spring Frost March 4
264 growing days
First Fall Frost November 23

Polk County Soil Profile

Soil Type

Sandy Loam

Soil pH

5.2-6.6

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (127 days to spare)
Start indoors: Jan 22 Transplant: Feb 19 🍅 Harvest: Jun 4 – Jul 9
Recommended (50%) ✓ Fits season (124 days to spare)
Start indoors: Feb 4 Transplant: Mar 4 🍅 Harvest: Jun 17 – Jul 22
Safe Start (90%) ✓ Fits season (119 days to spare)
Start indoors: Feb 28 Transplant: Mar 28 🍅 Harvest: Jul 11 – Aug 15

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 Polk County

How your county's soil matches Celeriac's growing requirements.

Soil pH

Your soil pH (5.2–6.6) is more acidic than Celeriac prefers (6.0–7.0). Add garden lime to raise pH.

Soil Texture

Sandy soil in Polk County warms quickly in spring but drains fast. Celeriac will need more frequent watering and regular compost additions to retain nutrients.

Drainage

Celeriac is a heavy drinker but your soil drains very quickly. Mulch heavily and consider drip irrigation.

Organic Matter

Organic matter is moderate (2.3%). Annual compost additions will help Celeriac.

How to Plant Celeriac

1"
Planting Depth
15"
Between Plants
24"
Between Rows

Fall planting: Sow 8 weeks before your first frost date for a fall harvest.

Plant Water Budget

Plant needs
0.9″/week
Rainfall provides
1.0″/week
You supply
0.2″/week
Watering frequency Only during dry spells
Season total 394 gal / 100 sq ft

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 1.4" 0" ❄️ Dormant
Feb 2.4" 0" ❄️ Dormant
Mar 3.9" 4" 0" ✅ Rainfall sufficient
Apr 3.9" 5.8" 0" ✅ Rainfall sufficient
May 3.9" 8.5" 0" ✅ Rainfall sufficient
Jun 3.9" 11.4" 0" ✅ Rainfall sufficient
Jul 3.9" 7" 0" ✅ Rainfall sufficient
Aug 3.9" 7.9" 0" ✅ Rainfall sufficient
Sep 3.9" 6.5" 0" ✅ Rainfall sufficient
Oct 3.9" 4.4" 0" ✅ Rainfall sufficient
Nov 3.9" 2.1" 1.8" 💧 Light watering
Dec 1.6" 0" ❄️ Dormant

Water needs are for active growing months only (Mar–Nov in Polk 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 needs ~2,420 GDD — county provides 5,808 GDD Excellent fit

Celeriac Planting Timeline — Polk County, TX

Celeriac Planting Calendar

Activity When Date Range
Start Indoors February 4 Feb 4 – Feb 18
Transplant Outdoors March 4 Mar 4 – Mar 18
Direct Sow February 11 Feb 11 – Mar 4
Harvest June 17 Jun 17 – Jul 22
Fall Sowing September 28 Sep 28 – Oct 12

Plant 1" deep · 15" apart · Rows 24" apart

Month-by-Month Timeline

MonthActivities
January
February Start Indoors Direct Sow
March Transplant Outdoors Direct Sow
April
May
June Harvest
July Harvest
August
September Fall Sowing
October Fall Sowing
November
December

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.9"/week · Only during dry spells

📅 Days to Maturity

100–120 days

🧪 Soil pH

Needs 6–7 · Your soil: too_acidic

🗺️ USDA Zone

Zone 9a

📆 Growing Season

264 days in Polk County

Growing Tips for Celeriac in Polk County

Direct sow Celeriac outdoors after March 04 in Polk County when soil has warmed and frost danger has passed.

Sandy soil in Polk County dries quickly — mulch Celeriac with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.

With summer highs reaching 96°F in Polk 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.

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

  • Carrots
  • Parsnip

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Celeriac in Polk County, TX?

Polk County is in Zone 9a with an average last frost of March 4. Plan your Celeriac planting based on this frost date — see the calendar above for exact timing.

What planting zone is Polk County, TX?

Polk County, Texas is in USDA Hardiness Zone 9a. The average last spring frost is March 4 and first fall frost is November 23.

🌱

Your Polk County Garden Planner — Free

A 24-page printable planner built for Polk 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.

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Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Polk County, TX. Local conditions may vary. Last updated: May 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.