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When to plant Watercress in Somerset County County,

Aim to plant Watercress in Somerset County County on or after May 8; the window stays open through May 29. Somerset County County's 127-day frost-free season gives you just enough for one full spring planting. A second sowing from July 18 to August 1 extends the harvest into fall.

When to Plant Watercress in Somerset County, ME

Somerset County, Maine Zone 5a June

Your June gardening checklist

Your garden in Somerset County, Maine is working on a schedule, even when you're not. Here's where you should be this June.

Avg. last frost May 22
Avg. first frost September 26
Soil temp (4") 66°F
Watering Low
Pest pressure High
Daylight 15.5 hrs
  1. Start watercress under lights

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

July will be here before you know it — start on
  • First harvests: watercress
  • Fall sowing: 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.

Somerset County, Maine is in USDA Zone 5a. The average last spring frost is May 22 and the first fall frost is September 26, giving you a growing season of approximately 127 days.

At an elevation of 356 feet, Somerset County receives approximately 48.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 80°F, so choose short-season varieties of Watercress to ensure they mature before fall.

Somerset County, ME (Zone 5a) Short season
127 days
Last Spring Frost May 22
127 growing days
First Fall Frost September 26
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Somerset County Soil Profile

Soil Type

Silt Loam

Soil pH

4.8-6.4

Drainage

Well Drained

Watercress Planting Risk Windows

Early Start (70% safe) ✓ Fits season (50 days to spare)
Start indoors: Apr 10 Transplant: May 15 🍅 Harvest: Jun 26 – Jul 31
Recommended (50%) ✓ Fits season (50 days to spare)
Start indoors: Apr 17 Transplant: May 22 🍅 Harvest: Jul 3 – Aug 7
Safe Start (90%) ✓ Fits season (53 days to spare)
Start indoors: Apr 29 Transplant: Jun 3 🍅 Harvest: Jul 15 – Aug 19

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 Somerset County

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

Soil pH

Your soil pH (4.8–6.4) is more acidic than Watercress prefers (6.5–7.5). Add garden lime to raise pH.

Soil Texture

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

Drainage

Drainage is adequate for Watercress.

Organic Matter

Organic matter is moderate (3.3%). 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

3
successive plantings in your 127-day season

Sow every 4.6 weeks. Last sowing by Jul 28 to harvest before frost.

For a dedicated fall crop, sow by Jul 18.

Watercress Water Budget

Plant needs
1.5″/week
Rainfall provides
1.6″/week
Watering frequency Natural rainfall sufficient
Season total 0 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 2.9" 0" ❄️ Dormant
Feb 3.2" 0" ❄️ Dormant
Mar 4.5" 0" ❄️ Dormant
Apr 4.6" 0" ❄️ Dormant
May 6.5" 4.2" 2.3" 💧 Light watering
Jun 6.5" 5" 1.5" 💧 Light watering
Jul 6.5" 4" 2.5" 💧 Light watering
Aug 6.5" 4.6" 1.9" 💧 Light watering
Sep 6.5" 4" 2.5" 💧 Light watering
Oct 4.2" 0" ❄️ Dormant
Nov 3.8" 0" ❄️ Dormant
Dec 3.9" 0" ❄️ Dormant

Water needs are for active growing months only (May–Sep in Somerset 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 ~500 GDD — county provides 1,270 GDD Excellent fit

Watercress Planting Timeline — Somerset County, ME

Watercress Planting Calendar

Activity When Date Range
Start Indoors April 17 Apr 17 – May 1
Transplant Outdoors May 22 May 22 – Jun 5
Direct Sow May 8 May 8 – May 29
Harvest July 3 Jul 3 – Aug 7
Fall Sowing July 18 Jul 18 – Aug 1

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

Month-by-Month Timeline

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

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

1.5"/week · Natural rainfall sufficient

📅 Days to Maturity

40–60 days

🧪 Soil pH

Needs 6.5–7.5 · Your soil: too_acidic

🗺️ USDA Zone

Zone 5a

📆 Growing Season

127 days in Somerset County

Growing Tips for Watercress in Somerset County

Direct sow Watercress outdoors after May 22 in Somerset County when soil has warmed and frost danger has passed.

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 Somerset County, ME?

Somerset County is in Zone 5a with an average last frost of May 22. Plan your Watercress planting based on this frost date — see the calendar above for exact timing.

What planting zone is Somerset County, ME?

Somerset County, Maine is in USDA Hardiness Zone 5a. The average last spring frost is May 22 and first fall frost is September 26.

When should I plant Watercress in Somerset County County, ?

In Somerset County County, , plant Watercress after the last frost (around May 22) and before the first frost (around September 26). Best results when soil holds above 50°F.

What growing zone is Somerset County County, for Watercress?

Somerset County County sits in USDA Zone 5a. Watercress grows reliably in zones 3a through 11b, so it's a good fit here.

Can Watercress grow in Somerset County County's climate?

Yes — Watercress grows well in Somerset County County's temperate climate. Somerset County County averages a 127-day frost-free season, with last frost around May 22 and first frost around September 26.

🌱

Your Somerset County Garden Planner — Free

A 22-page printable planner built for Somerset County (Zone 5a). 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 Somerset County, ME. Local conditions may vary. Last updated: June 2026.

Sources & credits

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