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When to Plant Microgreens in Washington County, VA

Washington County, Virginia Zone 7a May

What to do in May

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

Avg. last frost April 26
Avg. first frost October 17
Soil temp (4") 65°F
Watering Low
Pest pressure Low
Daylight 14 hrs
  1. Indoor seed-starting week for microgreens

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

  2. It's harvest week for microgreens

    This is the payoff month. Bring a basket, bring a friend, and get into the beds.

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Microgreens are young seedlings of vegetables and herbs harvested at the cotyledon or first true leaf stage. They pack concentrated flavors and nutrients in a tiny package.

Washington County, Virginia is in USDA Zone 7a. The average last spring frost is April 26 and the first fall frost is October 17, giving you a growing season of approximately 174 days.

At an elevation of 816 feet, Washington County receives approximately 54.4 inches of rainfall annually with predominantly silt loam soil. Summer highs average 90°F, providing good warmth for Microgreens during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Microgreens root diseases.

Washington County, VA (Zone 7a) Moderate season
174 days
Last Spring Frost April 26
174 growing days
First Fall Frost October 17

Washington County Soil Profile

Soil Type

Silt Loam

Soil pH

5.3-6.9

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (144 days to spare)
Start indoors: Mar 12 Transplant: Apr 16 🍅 Harvest: Apr 23 – May 21
Recommended (50%) ✓ Fits season (139 days to spare)
Start indoors: Mar 22 Transplant: Apr 26 🍅 Harvest: May 3 – May 31
Safe Start (90%) ✓ Fits season (135 days to spare)
Start indoors: Apr 10 Transplant: May 15 🍅 Harvest: May 22 – Jun 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 Washington County

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

Soil pH

Your soil pH (5.3–6.9) overlaps with Microgreens's range (6.0–7.0), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is moderate (2.6%). Annual compost additions will help Microgreens.

How to Plant Microgreens

0.5"
Planting Depth
2"
Between Plants
6"
Between Rows

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

Succession Planting Microgreens

34
successive plantings in your 174-day season

Sow every 0.7 weeks. Last sowing by Sep 26 to harvest before frost.

For a dedicated fall crop, sow by Aug 08.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
1.3″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft

Monthly Watering Guide for Microgreens

Microgreens needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Microgreens Needs Rainfall You Supplement Action
Jan 4" 0" ❄️ Dormant
Feb 4.8" 0" ❄️ Dormant
Mar 5.7" 0" ❄️ Dormant
Apr 4.3" 3.7" 0.6" 💧 Light watering
May 4.3" 4.6" 0" ✅ Rainfall sufficient
Jun 4.3" 5" 0" ✅ Rainfall sufficient
Jul 4.3" 6" 0" ✅ Rainfall sufficient
Aug 4.3" 5.8" 0" ✅ Rainfall sufficient
Sep 4.3" 3.5" 0.8" 💧 Light watering
Oct 4.3" 3" 1.3" 💧 Light watering
Nov 4.3" 0" ❄️ Dormant
Dec 4" 0" ❄️ Dormant

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

Microgreens 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.

Microgreens needs ~245 GDD — county provides 3,045 GDD Excellent fit

Microgreens Planting Timeline — Washington County, VA

Microgreens Planting Calendar

Activity When Date Range
Start Indoors March 22 Mar 22 – Apr 5
Transplant Outdoors April 26 Apr 26 – May 10
Direct Sow April 12 Apr 12 – May 3
Harvest May 3 May 3 – May 31
Fall Sowing August 8 Aug 8 – Aug 22

Plant 0.5" deep · 2" apart · Rows 6" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

1"/week · Natural rainfall sufficient

📅 Days to Maturity

7–21 days

🧪 Soil pH

Needs 6–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 7a

📆 Growing Season

174 days in Washington County

Growing Tips for Microgreens in Washington County

Direct sow Microgreens outdoors after April 26 in Washington County when soil has warmed and frost danger has passed.

Your generous 174.0-day season in Washington County allows multiple plantings of Microgreens. Sow every 3.0 days for continuous harvest.

General growing tips

Sow seeds densely on shallow trays of moist growing medium. Cover until germination, then provide light. Harvest with scissors when 1-3 inches tall. Grow year-round indoors.

Frequently Asked Questions

When should I plant Microgreens in Washington County, VA?

Washington County is in Zone 7a with an average last frost of April 26. Plan your Microgreens planting based on this frost date — see the calendar above for exact timing.

What planting zone is Washington County, VA?

Washington County, Virginia is in USDA Hardiness Zone 7a. The average last spring frost is April 26 and first fall frost is October 17.

🌱

Your Washington County Garden Planner — Free

A 24-page printable planner built for Washington 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 Washington County, VA. 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.