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When to Plant Arugula in Tillman County, OK

Tillman County, Oklahoma Zone 8a May

This month in Tillman County, Oklahoma

May is a pivotal month for Tillman County, Oklahoma gardens. Focus on these tasks first and you'll set up the rest of the season for success.

Avg. last frost April 3
Avg. first frost November 6
Soil temp (4") 68°F
Watering Moderate
Pest pressure Moderate
Daylight 13.8 hrs
  1. Fire up the seed-starting tray: arugula

    Bottom-water once the first true leaves appear — it keeps stems dry and knocks back damping-off.

  2. Start harvesting arugula

    Don't tug. Use scissors or pruners for clean cuts — torn stems invite disease.

Looking ahead to June
  • First harvests: arugula

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Arugula is a fast-growing cool-season green with a peppery, nutty flavor. It is excellent in salads and can be harvested as baby greens or mature leaves.

Tillman County, Oklahoma is in USDA Zone 8a. The average last spring frost is April 3 and the first fall frost is November 6, giving you a growing season of approximately 217 days.

At an elevation of 807 feet, Tillman County receives approximately 25.1 inches of rainfall annually with predominantly loam soil. Summer highs average 88°F, providing good warmth for Arugula during the growing season.

Tillman County, OK (Zone 8a) Long season
217 days
Last Spring Frost April 3
217 growing days
First Fall Frost November 6
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Tillman County Soil Profile

Soil Type

Loam

Soil pH

6.2-7.5

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (124 days to spare)
Start indoors: Feb 14 Transplant: Mar 21 🍅 Harvest: Apr 25 – Jun 27
Recommended (50%) ✓ Fits season (119 days to spare)
Start indoors: Feb 27 Transplant: Apr 3 🍅 Harvest: May 8 – Jul 10
Safe Start (90%) ✓ Fits season (124 days to spare)
Start indoors: Mar 11 Transplant: Apr 15 🍅 Harvest: May 20 – Jul 22

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 Tillman County

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

Soil pH

Your soil pH (6.2–7.5) overlaps with Arugula's range (6.0–7.0), though not a perfect match.

Soil Texture

The loam soil in Tillman County is excellent for Arugula — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (3.6%). Annual compost additions will help Arugula.

How to Plant Arugula

0.5"
Planting Depth
6"
Between Plants
12"
Between Rows

Fall planting: Sow 10 weeks before your first frost date for a fall harvest.

Succession Planting Arugula

8
successive plantings in your 217-day season

Sow every 3.4 weeks. Last sowing by Sep 17 to harvest before frost.

For a dedicated fall crop, sow by Aug 28.

Plant Water Budget

Plant needs
0.6″/week
Rainfall provides
0.5″/week
You supply
0.1″/week
Watering frequency Only during dry spells
Season total 221 gal / 100 sq ft

Monthly Watering Guide for Arugula

Arugula needs approximately 0.6 inches of water per week (2.6" per month). Here's how your county's rainfall compares month by month.

Month Arugula Needs Rainfall You Supplement Action
Jan 0.6" 0" ❄️ Dormant
Feb 0.9" 0" ❄️ Dormant
Mar 1.7" 0" ❄️ Dormant
Apr 2.6" 2.8" 0" ✅ Rainfall sufficient
May 2.6" 3.7" 0" ✅ Rainfall sufficient
Jun 2.6" 4" 0" ✅ Rainfall sufficient
Jul 2.6" 3.3" 0" ✅ Rainfall sufficient
Aug 2.6" 2.9" 0" ✅ Rainfall sufficient
Sep 2.6" 2" 0.6" 💧 Light watering
Oct 2.6" 1.6" 1" 💧 Light watering
Nov 2.6" 0.8" 1.8" 🚿 Regular watering
Dec 0.7" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Nov in Tillman County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Arugula 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.

Arugula needs ~640 GDD — county provides 3,472 GDD Excellent fit

Arugula Planting Timeline — Tillman County, OK

Arugula Planting Calendar

Activity When Date Range
Start Indoors February 27 Feb 27 – Mar 13
Transplant Outdoors April 3 Apr 3 – Apr 17
Direct Sow March 20 Mar 20 – Apr 10
Harvest May 8 May 8 – Jul 10
Fall Sowing August 28 Aug 28 – Sep 11

Plant 0.5" deep · 6" apart · Rows 12" apart

Month-by-Month Timeline

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

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

0.6"/week · Only during dry spells

📅 Days to Maturity

30–50 days

🧪 Soil pH

Needs 6–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 8a

📆 Growing Season

217 days in Tillman County

Growing Tips for Arugula in Tillman County

Direct sow Arugula outdoors after April 03 in Tillman County when soil has warmed and frost danger has passed.

Your generous 217.0-day season in Tillman County allows multiple plantings of Arugula. Sow every 15.0 days for continuous harvest.

Common pests for Arugula in this region include cabbage worm and flea beetles. Use row covers early in the season and inspect plants weekly.

General growing tips

Sow seeds directly every 2-3 weeks for continuous harvest. Provide afternoon shade in warm weather to prevent bolting. Harvest outer leaves first to extend production.

Companion Planting

Good Companions

Avoid Planting Near

  • Strawberries

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Arugula in Tillman County, OK?

Tillman County is in Zone 8a with an average last frost of April 3. Plan your Arugula planting based on this frost date — see the calendar above for exact timing.

What planting zone is Tillman County, OK?

Tillman County, Oklahoma is in USDA Hardiness Zone 8a. The average last spring frost is April 3 and first fall frost is November 6.

🌱

Your Tillman County Garden Planner — Free

A 24-page printable planner built for Tillman County (Zone 8a). 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 Tillman County, OK. 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.