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When to plant Mache in Mercer County, IL

In Mercer County, plant Mache in spring between April 3 and April 24, once soil temps hold above 50°F. Mercer County's last frost averages April 17, so time plantings around the expected last-frost window for best survival. For a fall crop, sow between August 6 and August 20 — roughly 40–60 days before the first frost on October 15.

When to Plant Mache in Mercer County, IL

Mache (corn salad) is a cold-hardy salad green with small, rounded, tender leaves and a mild, nutty flavor. It thrives in cool weather and even overwinters in many climates.

Mercer County, Illinois is in USDA Zone 5b. The average last spring frost is April 17 and the first fall frost is October 15, giving you a growing season of approximately 181 days.

At an elevation of 777 feet, Mercer County receives approximately 37.2 inches of rainfall annually with predominantly silt loam soil. Summer highs average 83°F, so choose short-season varieties of Mache to ensure they mature before fall.

Mercer County, IL (Zone 5b) Moderate season
181 days
Last Spring Frost April 17
181 growing days
First Fall Frost October 15

Mercer County Soil Profile

Soil Type

Silt Loam

Soil pH

6.3-6.7

Drainage

Well Drained

Monthly Watering Guide for Mache

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

Month Mache Needs Rainfall You Supplement Action
Jan 1.8" 0" ❄️ Dormant
Feb 1.8" 0" ❄️ Dormant
Mar 2.9" 0" ❄️ Dormant
Apr 4.3" 3.7" 0.6" 💧 Light watering
May 4.3" 4" 0.3" 💧 Light watering
Jun 4.3" 4.6" 0" ✅ Rainfall sufficient
Jul 4.3" 3.7" 0.6" 💧 Light watering
Aug 4.3" 4" 0.3" 💧 Light watering
Sep 4.3" 3.4" 0.9" 💧 Light watering
Oct 4.3" 2.5" 1.8" 💧 Light watering
Nov 2.6" 0" ❄️ Dormant
Dec 2.2" 0" ❄️ Dormant

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

Mache Planting Timeline — Mercer County, IL

Mache Planting Calendar

Activity When Date Range
Start Indoors March 13 Mar 13 – Mar 27
Transplant Outdoors April 17 Apr 17 – May 1
Direct Sow April 3 Apr 3 – Apr 24
Harvest May 29 May 29 – Jul 3
Fall Sowing August 6 Aug 6 – Aug 20

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

Moderate — regular watering

📅 Days to Maturity

40–60 days

🧪 Soil pH

Needs 6–7.5 · Your soil: N/A

🗺️ USDA Zone

Zone 5b

📆 Growing Season

181 days in Mercer County

Growing Tips for Mercer County

Direct sow in early spring or late summer for fall and winter harvest. Seeds need light to germinate so press gently into soil surface. Harvest whole rosettes.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Mache in Mercer County, IL?

Mercer County is in Zone 5b with an average last frost of April 17. Plan your Mache planting based on this frost date — see the calendar above for exact timing.

What planting zone is Mercer County, IL?

Mercer County, Illinois is in USDA Hardiness Zone 5b. The average last spring frost is April 17 and first fall frost is October 15.

When should I plant Mache in Mercer County, IL?

In Mercer County, IL, plant Mache after the last frost (around April 17) and before the first frost (around October 15). Best results when soil holds above 50°F.

What growing zone is Mercer County, IL for Mache?

Mercer County sits in USDA Zone 5b. Mache grows reliably in zones 2a through 10b, so it's a good fit here.

Can Mache grow in Mercer County's climate?

Yes — Mache grows well in Mercer County's temperate climate. Mercer County averages a 181-day frost-free season, with last frost around April 17 and first frost around October 15.

🌱

Your Mercer County Garden Planner — Free

A 22-page printable planner built for Mercer 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 Mercer County, IL. Local conditions may vary. Last updated: June 2026.

Sources & credits

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