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When to Plant Watercress in McDonald County, MO

McDonald County, Missouri Zone 7a May

May to-do list for McDonald County, Missouri

If you only do a handful of things in the garden this May, make it these. They're sequenced around your zone's frost timing.

Avg. last frost April 8
Avg. first frost October 27
Soil temp (4") 63°F
Watering Low
Pest pressure Low
Daylight 14 hrs
  1. Fire up the seed-starting tray: watercress

    Your window is short. These crops want several weeks of indoor growth before they go outside.

  2. Basket week: watercress

    The more you pick, the more the plant produces. Letting fruit overripen tells the plant it's time to stop.

June will be here before you know it — start on
  • First harvests: watercress

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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.

McDonald County, Missouri is in USDA Zone 7a. The average last spring frost is April 8 and the first fall frost is October 27, giving you a growing season of approximately 202 days.

At an elevation of 977 feet, McDonald County receives approximately 39.9 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85°F, providing good warmth for Watercress during the growing season.

McDonald County, MO (Zone 7a) Long season
202 days
Last Spring Frost April 8
202 growing days
First Fall Frost October 27
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McDonald County Soil Profile

Soil Type

Silt Loam

Soil pH

5.6-6.5

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (128 days to spare)
Start indoors: Feb 25 Transplant: Apr 1 🍅 Harvest: May 13 – Jun 17
Recommended (50%) ✓ Fits season (125 days to spare)
Start indoors: Mar 4 Transplant: Apr 8 🍅 Harvest: May 20 – Jun 24
Safe Start (90%) ✓ Fits season (125 days to spare)
Start indoors: Mar 17 Transplant: Apr 21 🍅 Harvest: Jun 2 – Jul 7

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 McDonald County

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

Soil pH

Your soil pH (5.6–6.5) is more acidic than Watercress prefers (6.5–7.5). Add garden lime to raise pH.

Soil Texture

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

Organic Matter

Organic matter is moderate (2.9%). 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 28 to harvest before frost.

For a dedicated fall crop, sow by Aug 18.

Plant Water Budget

Plant needs
1.5″/week
Rainfall provides
0.8″/week
You supply
0.8″/week
Watering frequency 2-3 times/week
Season total 1,446 gal / 100 sq ft
Drought risk

Water stress score is 6/10 — consider drought-tolerant varieties and mulching

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 1.7" 0" ❄️ Dormant
Feb 1.6" 0" ❄️ Dormant
Mar 2.5" 0" ❄️ Dormant
Apr 6.5" 3.7" 2.8" 💧 Light watering
May 6.5" 4.4" 2.1" 💧 Light watering
Jun 6.5" 4.3" 2.2" 💧 Light watering
Jul 6.5" 4.7" 1.8" 💧 Light watering
Aug 6.5" 4.6" 1.9" 💧 Light watering
Sep 6.5" 3.9" 2.6" 💧 Light watering
Oct 6.5" 3.3" 3.2" 💧 Light watering
Nov 3.1" 0" ❄️ Dormant
Dec 2.3" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in McDonald 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 ~688 GDD — county provides 2,777 GDD Excellent fit

Watercress Planting Timeline — McDonald County, MO

Watercress Planting Calendar

Activity When Date Range
Start Indoors March 4 Mar 4 – Mar 18
Transplant Outdoors April 8 Apr 8 – Apr 22
Direct Sow March 25 Mar 25 – Apr 15
Harvest May 20 May 20 – Jun 24
Fall Sowing August 18 Aug 18 – Sep 1

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
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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: too_acidic

🗺️ USDA Zone

Zone 7a

📆 Growing Season

202 days in McDonald County

Growing Tips for Watercress in McDonald County

Direct sow Watercress outdoors after April 08 in McDonald County when soil has warmed and frost danger has passed.

Your generous 202.0-day season in McDonald 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 McDonald County, MO?

McDonald County is in Zone 7a with an average last frost of April 8. Plan your Watercress planting based on this frost date — see the calendar above for exact timing.

What planting zone is McDonald County, MO?

McDonald County, Missouri is in USDA Hardiness Zone 7a. The average last spring frost is April 8 and first fall frost is October 27.

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Your McDonald County Garden Planner — Free

A 24-page printable planner built for McDonald 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.

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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 McDonald County, MO. 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.