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When to Plant Microgreens in Rockbridge County, VA

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.

Rockbridge County, Virginia is in USDA Zone 6b. The average last spring frost is April 21 and the first fall frost is October 22, giving you a growing season of approximately 184 days.

At an elevation of 159 feet, Rockbridge County receives approximately 46.2 inches of rainfall annually with predominantly silt loam soil. Summer highs average 88ยฐF, providing good warmth for Microgreens during the growing season.

Rockbridge County, VA (Zone 6b) Moderate season
184 days
Last Spring Frost April 21
184 growing days
First Fall Frost October 22

Rockbridge County Soil Profile

Soil Type

Silt Loam

Soil pH

5.5-6.5

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (152 days to spare)
Start indoors: Mar 10 Transplant: Apr 14 🍅 Harvest: Apr 21 – May 19
Recommended (50%) ✓ Fits season (149 days to spare)
Start indoors: Mar 17 Transplant: Apr 21 🍅 Harvest: Apr 28 – May 26
Safe Start (90%) ✓ Fits season (140 days to spare)
Start indoors: Apr 9 Transplant: May 14 🍅 Harvest: May 21 – Jun 18

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 Rockbridge County

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

Soil pH

Your soil pH (5.5โ€“6.5) overlaps with Microgreens's range (6.0โ€“7.0), though not a perfect match.

Soil Texture

The silt loam soil in Rockbridge County is excellent for Microgreens โ€” good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (3.1%). 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

36
successive plantings in your 184-day season

Sow every 0.7 weeks. Last sowing by Oct 01 to harvest before frost.

For a dedicated fall crop, sow by Aug 13.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
1.1″/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 โ€” 3.9" 0" โ„๏ธ Dormant
Feb โ€” 3.8" 0" โ„๏ธ Dormant
Mar โ€” 4.9" 0" โ„๏ธ Dormant
Apr 4.3" 3.2" 1.1" ๐Ÿ’ง Light watering
May 4.3" 4.3" 0" โœ… Rainfall sufficient
Jun 4.3" 3.8" 0.5" ๐Ÿ’ง Light watering
Jul 4.3" 4.4" 0" โœ… Rainfall sufficient
Aug 4.3" 4.6" 0" โœ… Rainfall sufficient
Sep 4.3" 3.8" 0.5" ๐Ÿ’ง Light watering
Oct 4.3" 2.7" 1.6" ๐Ÿ’ง Light watering
Nov โ€” 3.2" 0" โ„๏ธ Dormant
Dec โ€” 3.7" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Aprโ€“Oct in Rockbridge County). Supplement amounts are based on average rainfall โ€” 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" โ€” every day above 50ยฐF 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 ~224 GDD — county provides 2,944 GDD Excellent fit

Microgreens Planting Timeline โ€” Rockbridge County, VA

Microgreens Planting Calendar

Activity When Date Range
Start Indoors March 17 Mar 17 โ€“ Mar 31
Transplant Outdoors April 21 Apr 21 โ€“ May 5
Direct Sow April 7 Apr 7 โ€“ Apr 28
Harvest April 28 Apr 28 โ€“ May 26
Fall Sowing August 13 Aug 13 โ€“ Aug 27

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

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Partial Shade (3-6 hours)

๐Ÿ’ง Water

1"/week ยท Natural rainfall sufficient

๐Ÿ“… Days to Maturity

7โ€“21 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 6b

๐Ÿ“† Growing Season

184 days in Rockbridge County

Growing Tips for Microgreens in Rockbridge County

Direct sow Microgreens outdoors after April 21 in Rockbridge County when soil has warmed and frost danger has passed.

Your generous 184.0-day season in Rockbridge 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 Rockbridge County, VA?

Rockbridge County is in Zone 6b with an average last frost of April 21. Plan your Microgreens planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Rockbridge County, VA?

Rockbridge County, Virginia is in USDA Hardiness Zone 6b. The average last spring frost is April 21 and first fall frost is October 22.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Rockbridge County gardeners in Zone 6b organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

Free download. Plan your entire garden season in minutes.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Rockbridge County, VA. Local conditions may vary. Last updated: April 2026.