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When to Plant Microgreens in Martin County, TX

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.

Martin County, Texas is in USDA Zone 7b. The average last spring frost is March 25 and the first fall frost is November 12, giving you a growing season of approximately 232 days.

At an elevation of 4,922 feet, Martin County receives approximately 50.2 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 100ยฐF, so Microgreens may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring โ€” great for early planting โ€” but Microgreens will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Microgreens root diseases.

Martin County, TX (Zone 7b) Long season
232 days
Last Spring Frost March 25
232 growing days
First Fall Frost November 12

Martin County Soil Profile

Soil Type

Sandy Loam

Soil pH

7.2-8.7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (195 days to spare)
Start indoors: Feb 10 Transplant: Mar 17 🍅 Harvest: Mar 24 – Apr 21
Recommended (50%) ✓ Fits season (197 days to spare)
Start indoors: Feb 18 Transplant: Mar 25 🍅 Harvest: Apr 1 – Apr 29
Safe Start (90%) ✓ Fits season (191 days to spare)
Start indoors: Mar 9 Transplant: Apr 13 🍅 Harvest: Apr 20 – May 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 Martin County

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

Soil pH

Your soil pH (7.2โ€“8.7) is more alkaline than Microgreens prefers (6.0โ€“7.0). Add sulfur or peat moss to lower pH.

Soil Texture

Sandy soil in Martin County warms quickly in spring but drains fast. Microgreens will need more frequent watering and regular compost additions to retain nutrients.

Organic Matter

Organic matter is low (1.0%). Add 2-3 inches of compost before planting 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

46
successive plantings in your 232-day season

Sow every 0.7 weeks. Last sowing by Oct 22 to harvest before frost.

For a dedicated fall crop, sow by Sep 03.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.9″/week
You supply
0.1″/week
Watering frequency Only during dry spells
Season total 226 gal / 100 sq ft
Drought risk

Water stress score is 8/10 โ€” consider drought-tolerant varieties and mulching

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€” 2.9" 0" โ„๏ธ Dormant
Feb โ€” 3" 0" โ„๏ธ Dormant
Mar 4.3" 2.4" 1.9" ๐Ÿ’ง Light watering
Apr 4.3" 1.9" 2.4" ๐Ÿšฟ Regular watering
May 4.3" 0.9" 3.4" ๐Ÿšฟ Regular watering
Jun 4.3" 1.4" 2.9" ๐Ÿšฟ Regular watering
Jul 4.3" 9.2" 0" โœ… Rainfall sufficient
Aug 4.3" 10.1" 0" โœ… Rainfall sufficient
Sep 4.3" 7" 0" โœ… Rainfall sufficient
Oct 4.3" 4.9" 0" โœ… Rainfall sufficient
Nov 4.3" 2.8" 1.5" ๐Ÿ’ง Light watering
Dec โ€” 3.7" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Marโ€“Nov in Martin 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 ~350 GDD — county provides 5,800 GDD Excellent fit

Microgreens Planting Timeline โ€” Martin County, TX

Microgreens Planting Calendar

Activity When Date Range
Start Indoors February 18 Feb 18 โ€“ Mar 4
Transplant Outdoors March 25 Mar 25 โ€“ Apr 8
Direct Sow March 11 Mar 11 โ€“ Apr 1
Harvest April 1 Apr 1 โ€“ Apr 29
Fall Sowing September 3 Sep 3 โ€“ Sep 17

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

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Partial Shade (3-6 hours)

๐Ÿ’ง Water

1"/week ยท Only during dry spells

๐Ÿ“… Days to Maturity

7โ€“21 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: too_alkaline

๐Ÿ—บ๏ธ USDA Zone

Zone 7b

๐Ÿ“† Growing Season

232 days in Martin County

Growing Tips for Microgreens in Martin County

Direct sow Microgreens outdoors after March 25 in Martin County when soil has warmed and frost danger has passed.

Sandy soil in Martin County dries quickly โ€” mulch Microgreens with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.

With summer highs reaching 100ยฐF in Martin County, provide afternoon shade for Microgreens and water deeply in the morning.

Your generous 232.0-day season in Martin 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 Martin County, TX?

Martin County is in Zone 7b with an average last frost of March 25. Plan your Microgreens planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Martin County, TX?

Martin County, Texas is in USDA Hardiness Zone 7b. The average last spring frost is March 25 and first fall frost is November 12.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Martin County gardeners in Zone 7b organize planting dates, track what's growing, and never miss a planting window.

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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 Martin County, TX. Local conditions may vary. Last updated: April 2026.