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When to Plant Lettuce in Moose Jaw, SK

Lettuce

Lettuce is a fast-growing cool-season green available in leaf, romaine, butterhead, and crisphead types. It is the foundation of salads and one of the easiest crops to grow.

Moose Jaw, Saskatchewan is in USDA Zone 4a. The average last spring frost is May 16 and the first fall frost is October 3, giving you a growing season of approximately 140 days.

At an elevation of 1,893 feet, Moose Jaw receives approximately 14.2 inches of rainfall annually with predominantly dark brown chernozem soil. Summer highs average 71°F, so choose short-season varieties of Lettuce to ensure they mature before fall. With low rainfall, drip irrigation is essential for growing Lettuce successfully. Mulch heavily to conserve soil moisture.

Moose Jaw, SK (Zone 4a) Short season
140 days
Last Spring Frost May 16
140 growing days
First Fall Frost October 3
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Moose Jaw Soil Profile

Soil Type

Dark Brown Chernozem

Soil pH

6.0-7.0

Drainage

Well Drained

Lettuce Planting Risk Windows

Early Start (70% safe) ✓ Fits season (78 days to spare)
Start indoors: Mar 4 Transplant: Apr 15 🍅 Harvest: May 20 – Jul 29
Recommended (50%) ✓ Fits season (78 days to spare)
Start indoors: Mar 4 Transplant: Apr 15 🍅 Harvest: May 20 – Jul 29
Safe Start (90%) ✓ Fits season (78 days to spare)
Start indoors: Mar 4 Transplant: Apr 15 🍅 Harvest: May 20 – Jul 29

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 Lettuce

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

Fall planting: Sow 12 weeks before your first frost date for a fall harvest.

Lettuce Water Budget

Plant needs
0.7″/week
Rainfall provides
0.4″/week
You supply
0.3″/week
Watering frequency Only during dry spells
Season total 341 gal / 100 sq ft

Monthly Watering Guide for Lettuce

Lettuce needs approximately 0.7 inches of water per week (3" per month). Here's how your county's rainfall compares month by month.

Month Lettuce Needs Rainfall You Supplement Action
Jan 0.6" 0" ❄️ Dormant
Feb 0.7" 0" ❄️ Dormant
Mar 1.1" 0" ❄️ Dormant
Apr 1.2" 0" ❄️ Dormant
May 3" 1.5" 1.5" 🚿 Regular watering
Jun 3" 1.6" 1.4" 💧 Light watering
Jul 3" 1.5" 1.5" 🚿 Regular watering
Aug 3" 1.6" 1.4" 💧 Light watering
Sep 3" 1.4" 1.6" 🚿 Regular watering
Oct 3" 1.1" 1.9" 🚿 Regular watering
Nov 1.1" 0" ❄️ Dormant
Dec 0.7" 0" ❄️ Dormant

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

Lettuce 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" — every day above 50°F 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.

Lettuce needs ~146 GDD — county provides 455 GDD Excellent fit

Lettuce Planting Timeline — Moose Jaw, SK

Lettuce Planting Calendar

Activity When Date Range
Start Indoors April 4 Apr 4 – Apr 18
Transplant Outdoors May 16 May 16 – May 30
Direct Sow May 9 May 9 – May 30
Harvest June 20 Jun 20 – Aug 29
Fall Sowing July 11 Jul 11 – Jul 25

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

Month-by-Month Timeline

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

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

0.7"/week · Only during dry spells

📅 Days to Maturity

30–60 days

🧪 Soil pH

Needs 6–7 · Your soil: N/A

🗺️ USDA Zone

Zone 4a

📆 Growing Season

140 days in Moose Jaw

Growing Tips for Lettuce in Moose Jaw

Common pests for Lettuce in this region include aphids and slugs. Use row covers early in the season and inspect plants weekly.

General growing tips

Sow seeds directly every 2 weeks for continuous harvest. Provide afternoon shade in warm weather to delay bolting. Harvest in the morning for crispest leaves.

Companion Planting

Good Companions

Avoid Planting Near

  • Celery

Check more plant combinations with our Companion Planting Checker →

🌾 Save Your Own Lettuce Seeds
Life Cycle Annual
Pollination Self-Pollinating
How to Collect Let plants bolt and flower. Harvest seed heads when fluffy.
Storage Store airtight; viable 6 years at 35°F, under 45% humidity.

Very easy to save. Let a few plants bolt each season.

Frequently Asked Questions

When should I plant Lettuce in Moose Jaw, SK?

Moose Jaw is in Zone 4a with an average last frost of May 16. Plan your Lettuce planting based on this frost date — see the calendar above for exact timing.

What planting zone is Moose Jaw, SK?

Moose Jaw, Saskatchewan is in USDA Hardiness Zone 4a. The average last spring frost is May 16 and first fall frost is October 3.

🌱

Your Moose Jaw Garden Planner — Free

A 22-page printable planner built for Moose Jaw (Zone 4a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

Instant PDF download. No spam, unsubscribe any time.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Moose Jaw, SK. Local conditions may vary. Last updated: June 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.