Blog

When to Plant Watercress in Major County, OK

Major County, Oklahoma Zone 7a May

Your May gardening checklist

Welcome to May in Zone 7a. These are the moves that will have the biggest impact on your growing season.

Avg. last frost April 9
Avg. first frost October 28
Soil temp (4") 67°F
Watering Low
Pest pressure Moderate
Daylight 13.9 hrs
  1. Sow watercress in trays indoors

    Label every cell. You will absolutely forget which is which otherwise.

  2. It's harvest week for watercress

    Morning harvests are best — cooler temperatures mean crisper produce and longer fridge life.

Before June arrives, get these ready
  • First harvests: watercress

Instant PDF download. No spam, unsubscribe any time.

Watercress is a semi-aquatic plant with a peppery, tangy flavor rich in vitamins and minerals. It grows naturally along streams and can be cultivated in containers with standing water.

Major County, Oklahoma is in USDA Zone 7a. The average last spring frost is April 9 and the first fall frost is October 28, giving you a growing season of approximately 202 days.

At an elevation of 752 feet, Major County receives approximately 29.6 inches of rainfall annually with predominantly loam soil. Summer highs average 88°F, providing good warmth for Watercress during the growing season.

Major County, OK (Zone 7a) Long season
202 days
Last Spring Frost April 9
202 growing days
First Fall Frost October 28

Major County Soil Profile

Soil Type

Loam

Soil pH

6.8-7.4

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (125 days to spare)
Start indoors: Feb 28 Transplant: Apr 4 🍅 Harvest: May 16 – Jun 20
Recommended (50%) ✓ Fits season (125 days to spare)
Start indoors: Mar 5 Transplant: Apr 9 🍅 Harvest: May 21 – Jun 25
Safe Start (90%) ✓ Fits season (130 days to spare)
Start indoors: Mar 18 Transplant: Apr 22 🍅 Harvest: Jun 3 – Jul 8

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 Major County

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

Soil pH

Your soil pH (6.8–7.4) is within Watercress's preferred range (6.5–7.5).

Soil Texture

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

Drainage

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

Organic Matter

Organic matter is moderate (3.8%). Annual compost additions will help Watercress.

How to Plant Watercress

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 Watercress

6
successive plantings in your 202-day season

Sow every 4.6 weeks. Last sowing by Aug 29 to harvest before frost.

For a dedicated fall crop, sow by Aug 19.

Plant Water Budget

Plant needs
1.5″/week
Rainfall provides
0.6″/week
You supply
1.3″/week
Watering frequency 2-3 times/week
Season total 2,399 gal / 100 sq ft

Monthly Watering Guide for Watercress

Watercress needs approximately 1.5 inches of water per week (6.5" per month). Here's how your county's rainfall compares month by month.

Month Watercress Needs Rainfall You Supplement Action
Jan 0.9" 0" ❄️ Dormant
Feb 0.9" 0" ❄️ Dormant
Mar 2" 0" ❄️ Dormant
Apr 6.5" 2.9" 3.6" 🚿 Regular watering
May 6.5" 4.3" 2.2" 💧 Light watering
Jun 6.5" 5" 1.5" 💧 Light watering
Jul 6.5" 3.4" 3.1" 💧 Light watering
Aug 6.5" 3.6" 2.9" 💧 Light watering
Sep 6.5" 2.7" 3.8" 🚿 Regular watering
Oct 6.5" 2.1" 4.4" 🚿 Regular watering
Nov 1" 0" ❄️ Dormant
Dec 0.8" 0" ❄️ Dormant

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

Watercress 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.

Watercress needs ~800 GDD — county provides 3,232 GDD Excellent fit

Watercress Planting Timeline — Major County, OK

Watercress Planting Calendar

Activity When Date Range
Start Indoors March 5 Mar 5 – Mar 19
Transplant Outdoors April 9 Apr 9 – Apr 23
Direct Sow March 26 Mar 26 – Apr 16
Harvest May 21 May 21 – Jun 25
Fall Sowing August 19 Aug 19 – Sep 2

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

1.5"/week · 2-3 times/week

📅 Days to Maturity

40–60 days

🧪 Soil pH

Needs 6.5–7.5 · Your soil: ideal

🗺️ USDA Zone

Zone 7a

📆 Growing Season

202 days in Major County

Growing Tips for Watercress in Major County

Direct sow Watercress outdoors after April 09 in Major County when soil has warmed and frost danger has passed.

Your generous 202.0-day season in Major County allows multiple plantings of Watercress. Sow every 20.0 days for continuous harvest.

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

General growing tips

Grow in containers with trays of water kept fresh. Provide partial shade and cool conditions. Harvest stems by cutting above water level. Replace water frequently to prevent stagnation.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Watercress in Major County, OK?

Major County is in Zone 7a with an average last frost of April 9. Plan your Watercress planting based on this frost date — see the calendar above for exact timing.

What planting zone is Major County, OK?

Major County, Oklahoma is in USDA Hardiness Zone 7a. The average last spring frost is April 9 and first fall frost is October 28.

🌱

Your Major County Garden Planner — Free

A 24-page printable planner built for Major County (Zone 7a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

Instant PDF download. No spam, unsubscribe any time.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Major 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.