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When to Plant Mache in Lethbridge, AB

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.

Lethbridge, Alberta is in USDA Zone 5a. The average last spring frost is May 5 and the first fall frost is October 12, giving you a growing season of approximately 160 days.

At an elevation of 2,985 feet, Lethbridge receives approximately 23.7 inches of rainfall annually with predominantly dark brown chernozem soil. Summer highs average 74ยฐF, so choose short-season varieties of Mache to ensure they mature before fall.

Lethbridge, AB (Zone 5a) Moderate season
160 days
Last Spring Frost May 5
160 growing days
First Fall Frost October 12

Lethbridge Soil Profile

Soil Type

Dark Brown Chernozem

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
0.6″/week
You supply
0.4″/week
Watering frequency 1-2 times/week
Season total 538 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€” 0.9" 0" โ„๏ธ Dormant
Feb โ€” 1" 0" โ„๏ธ Dormant
Mar โ€” 1.8" 0" โ„๏ธ Dormant
Apr โ€” 2.4" 0" โ„๏ธ Dormant
May 4.3" 3.1" 1.2" ๐Ÿ’ง Light watering
Jun 4.3" 2.8" 1.5" ๐Ÿ’ง Light watering
Jul 4.3" 2.4" 1.9" ๐Ÿ’ง Light watering
Aug 4.3" 2.3" 2" ๐Ÿ’ง Light watering
Sep 4.3" 2.1" 2.2" ๐Ÿšฟ Regular watering
Oct 4.3" 2.1" 2.2" ๐Ÿšฟ Regular watering
Nov โ€” 1.5" 0" โ„๏ธ Dormant
Dec โ€” 1.4" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Mayโ€“Oct in Lethbridge). 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 ~275 GDD — county provides 880 GDD Excellent fit

Mache Planting Timeline โ€” Lethbridge, AB

Mache Planting Calendar

Activity When Date Range
Start Indoors March 31 Mar 31 โ€“ Apr 14
Transplant Outdoors May 5 May 5 โ€“ May 19
Direct Sow April 21 Apr 21 โ€“ May 12
Harvest June 16 Jun 16 โ€“ Jul 21
Fall Sowing August 3 Aug 3 โ€“ Aug 17

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

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March Start Indoors
April Start Indoors Direct Sow
May Transplant Outdoors Direct Sow
June Harvest
July Harvest
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 1-2 times/week

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 5a

๐Ÿ“† Growing Season

160 days in Lethbridge

Growing Tips for Mache in Lethbridge

Your generous 160.0-day season in Lethbridge allows multiple plantings of Mache. Sow every 20.0 days for continuous harvest.

Lethbridge receives only 24" of rain annually. Mache needs consistent moisture โ€” install drip irrigation or water deeply 2-3 times per week.

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 Lethbridge, AB?

Lethbridge is in Zone 5a with an average last frost of May 5. Plan your Mache planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Lethbridge, AB?

Lethbridge, Alberta is in USDA Hardiness Zone 5a. The average last spring frost is May 5 and first fall frost is October 12.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Lethbridge gardeners in Zone 5a 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 Lethbridge, AB. Local conditions may vary. Last updated: April 2026.