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When to plant Microgreens in LaSalle County, IL

The best window to plant Microgreens in LaSalle County, is April 8–April 29, when soil warms to 50°F. Last frost typically hits April 22; first frost October 14. A second sowing from August 5 to August 19 extends the harvest into fall.

When to Plant Microgreens in LaSalle County, IL

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.

LaSalle County, Illinois is in USDA Zone 5b. The average last spring frost is April 22 and the first fall frost is October 14, giving you a growing season of approximately 175 days.

At an elevation of 523 feet, LaSalle County receives approximately 39.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 84°F, so choose short-season varieties of Microgreens to ensure they mature before fall.

LaSalle County, IL (Zone 5b) Moderate season
175 days
Last Spring Frost April 22
175 growing days
First Fall Frost October 14

LaSalle County Soil Profile

Soil Type

Silt Loam

Soil pH

5.7-6.9

Drainage

Well Drained

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 1.5" 0" ❄️ Dormant
Feb 2" 0" ❄️ Dormant
Mar 2.5" 0" ❄️ Dormant
Apr 4.3" 4.2" 0.1" 💧 Light watering
May 4.3" 4.5" 0" ✅ Rainfall sufficient
Jun 4.3" 4.9" 0" ✅ Rainfall sufficient
Jul 4.3" 4.2" 0.1" 💧 Light watering
Aug 4.3" 3.7" 0.6" 💧 Light watering
Sep 4.3" 3.4" 0.9" 💧 Light watering
Oct 4.3" 3.7" 0.6" 💧 Light watering
Nov 2.7" 0" ❄️ Dormant
Dec 2.4" 0" ❄️ Dormant

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

Microgreens Planting Timeline — LaSalle County, IL

Microgreens Planting Calendar

Activity When Date Range
Start Indoors March 18 Mar 18 – Apr 1
Transplant Outdoors April 22 Apr 22 – May 6
Direct Sow April 8 Apr 8 – Apr 29
Harvest April 29 Apr 29 – May 27
Fall Sowing August 5 Aug 5 – Aug 19

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 Harvest
May Transplant Outdoors Harvest
June
July
August Fall Sowing
September
October
November
December

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

Moderate — regular watering

📅 Days to Maturity

7–21 days

🧪 Soil pH

Needs 6–7 · Your soil: N/A

🗺️ USDA Zone

Zone 5b

📆 Growing Season

175 days in LaSalle County

Growing Tips for LaSalle County

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 LaSalle County, IL?

LaSalle County is in Zone 5b with an average last frost of April 22. Plan your Microgreens planting based on this frost date — see the calendar above for exact timing.

What planting zone is LaSalle County, IL?

LaSalle County, Illinois is in USDA Hardiness Zone 5b. The average last spring frost is April 22 and first fall frost is October 14.

When should I plant Microgreens in LaSalle County, IL?

In LaSalle County, IL, plant Microgreens after the last frost (around April 22) and before the first frost (around October 14). Best results when soil holds above 50°F.

What growing zone is LaSalle County, IL for Microgreens?

LaSalle County sits in USDA Zone 5b. Microgreens grows reliably in zones 1a through 13b, so it's a good fit here.

Can Microgreens grow in LaSalle County's climate?

Yes — Microgreens grows well in LaSalle County's temperate climate. LaSalle County averages a 175-day frost-free season, with last frost around April 22 and first frost around October 14.

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Your LaSalle County Garden Planner — Free

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

Sources & credits

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