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When to Plant Mache in Kingston, ON

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.

Kingston, Ontario is in USDA Zone 6b. The average last spring frost is April 13 and the first fall frost is October 17, giving you a growing season of approximately 187 days.

At an elevation of 305 feet, Kingston receives approximately 36.6 inches of rainfall annually with predominantly clay loam soil. Summer highs average 84ยฐF, so choose short-season varieties of Mache to ensure they mature before fall. Clay soil retains moisture well for Mache, but amend with compost to improve drainage and prevent root rot.

Kingston, ON (Zone 6b) Moderate season
187 days
Last Spring Frost April 13
187 growing days
First Fall Frost October 17

Kingston Soil Profile

Soil Type

Clay Loam

Soil pH

6.0-7.0

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (106 days to spare)
Start indoors: Mar 11 Transplant: Apr 15 🍅 Harvest: May 27 – Jul 1
Recommended (50%) ✓ Fits season (106 days to spare)
Start indoors: Mar 11 Transplant: Apr 15 🍅 Harvest: May 27 – Jul 1
Safe Start (90%) ✓ Fits season (106 days to spare)
Start indoors: Mar 11 Transplant: Apr 15 🍅 Harvest: May 27 – Jul 1

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.

How to Plant Mache

0.5"
Planting Depth
6"
Between Plants
12"
Between Rows

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

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.8″/week
You supply
0.2″/week
Watering frequency Only during dry spells
Season total 296 gal / 100 sq ft

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 โ€” 1.5" 0" โ„๏ธ Dormant
Feb โ€” 1.8" 0" โ„๏ธ Dormant
Mar โ€” 2.2" 0" โ„๏ธ Dormant
Apr 4.3" 3.6" 0.7" ๐Ÿ’ง Light watering
May 4.3" 4.3" 0" โœ… Rainfall sufficient
Jun 4.3" 4.9" 0" โœ… Rainfall sufficient
Jul 4.3" 4.3" 0" โœ… Rainfall sufficient
Aug 4.3" 4.2" 0.1" ๐Ÿ’ง Light watering
Sep 4.3" 2.9" 1.4" ๐Ÿ’ง Light watering
Oct 4.3" 2.6" 1.7" ๐Ÿ’ง Light watering
Nov โ€” 2.2" 0" โ„๏ธ Dormant
Dec โ€” 2" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Aprโ€“Oct in Kingston). Supplement amounts are based on average rainfall โ€” actual needs vary with temperature, soil, and mulching.

Mache 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.

Mache needs ~650 GDD — county provides 2,431 GDD Excellent fit

Mache Planting Timeline โ€” Kingston, ON

Mache Planting Calendar

Activity When Date Range
Start Indoors March 9 Mar 9 โ€“ Mar 23
Transplant Outdoors April 13 Apr 13 โ€“ Apr 27
Direct Sow March 30 Mar 30 โ€“ Apr 20
Harvest May 25 May 25 โ€“ Jun 29
Fall Sowing August 8 Aug 8 โ€“ Aug 22

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

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March Start Indoors Direct Sow
April Transplant Outdoors Direct Sow
May Harvest
June Harvest
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 Only during dry spells

๐Ÿ“… Days to Maturity

40โ€“60 days

๐Ÿงช Soil pH

Needs 6โ€“7.5 ยท Your soil: N/A

๐Ÿ—บ๏ธ USDA Zone

Zone 6b

๐Ÿ“† Growing Season

187 days in Kingston

Growing Tips for Mache in Kingston

Your generous 187.0-day season in Kingston allows multiple plantings of Mache. Sow every 20.0 days for continuous harvest.

General growing tips

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 Kingston, ON?

Kingston is in Zone 6b with an average last frost of April 13. Plan your Mache planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Kingston, ON?

Kingston, Ontario is in USDA Hardiness Zone 6b. The average last spring frost is April 13 and first fall frost is October 17.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Kingston gardeners in Zone 6b 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 Kingston, ON. Local conditions may vary. Last updated: April 2026.