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When to Plant Nasturtium in Swift Current, SK

Nasturtium (Tropaeolum majus) is a fast-growing annual with distinctive round, lily-pad leaves and bold trumpet-shaped blooms in warm oranges, reds, and yellows. Both the flowers and leaves are edible with a peppery watercress flavor. Planted near vegetables, nasturtiums act as a sacrifice trap-crop, luring aphids away from more valuable plants. They thrive in poor, dry soil — rich conditions produce lush foliage but few flowers.

Swift Current, 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 2,680 feet, Swift Current receives approximately 15.3 inches of rainfall annually with predominantly dark brown chernozem soil. Summer highs average 75°F, so choose short-season varieties of Nasturtium to ensure they mature before fall. With low rainfall, drip irrigation is essential for growing Nasturtium successfully. Mulch heavily to conserve soil moisture.

Annual Blooms in Multi-season Pollinator-friendly Deer-resistant Good for cutting Fragrant
Swift Current, SK (Zone 4a) Short season
140 days
Last Spring Frost May 16
140 growing days
First Fall Frost October 3

Swift Current Soil Profile

Soil Type

Dark Brown Chernozem

Soil pH

6.0-7.0

Drainage

Well Drained

Nasturtium Planting Risk Windows

Early Start (70% safe) ✓ Fits season (36 days to spare)
Start indoors: Mar 18 Transplant: Apr 29 🌸 Bloom: Jun 24 – Sep 9
Recommended (50%) ✓ Fits season (36 days to spare)
Start indoors: Mar 18 Transplant: Apr 29 🌸 Bloom: Jun 24 – Sep 9
Safe Start (90%) ✓ Fits season (36 days to spare)
Start indoors: Mar 18 Transplant: Apr 29 🌸 Bloom: Jun 24 – Sep 9

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 Nasturtium

0.5"
Planting Depth
10"
Between Plants
12"
Between Rows

Nasturtium Water Budget

Plant needs
0.5″/week
Rainfall provides
0.5″/week
You supply
0.0″/week
Watering frequency Only during dry spells
Season total 51 gal / 100 sq ft

Monthly Watering Guide for Nasturtium

Nasturtium needs approximately 0.5 inches of water per week (2.2" per month). Here's how your county's rainfall compares month by month.

Month Nasturtium Needs Rainfall You Supplement Action
Jan 0.7" 0" ❄️ Dormant
Feb 0.5" 0" ❄️ Dormant
Mar 1.1" 0" ❄️ Dormant
Apr 1.5" 0" ❄️ Dormant
May 2.2" 1.9" 0.3" 💧 Light watering
Jun 2.2" 1.8" 0.4" 💧 Light watering
Jul 2.2" 1.8" 0.4" 💧 Light watering
Aug 2.2" 1.6" 0.6" 💧 Light watering
Sep 2.2" 1.3" 0.9" 💧 Light watering
Oct 2.2" 1.2" 1" 💧 Light watering
Nov 0.9" 0" ❄️ Dormant
Dec 0.8" 0" ❄️ Dormant

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

Nasturtium 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.

Nasturtium needs ~375 GDD — county provides 875 GDD Excellent fit

Nasturtium Planting Timeline — Swift Current, SK

Nasturtium Planting Calendar

Activity When Date Range
Start Indoors April 18 Apr 18 – May 2
Transplant Outdoors May 30 May 30 – Jun 13
Direct Sow May 30 May 30 – Jun 20
Bloom July 25 Jul 25 – Oct 10

Plant 0.5" deep · 10" apart · Rows 12" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.5"/week · Only during dry spells

📅 Days to Maturity

55–65 days

🧪 Soil pH

Needs 6–8 · Your soil: N/A

🗺️ USDA Zone

Zone 4a

📆 Growing Season

140 days in Swift Current

Growing Tips for Nasturtium in Swift Current

Swift Current receives only 15" of rain annually. Nasturtium needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.

General growing tips

Direct-sow large seeds 1/2 inch deep after last frost; soak seeds overnight to speed germination (7-10 days). Nasturtiums dislike root disturbance so direct sowing is strongly preferred. Avoid fertilizing — poor soil brings the best bloom. Trailing types can cover banks and climb trellises; dwarf types suit containers. In hot climates (zones 9+) plant in fall for winter/spring bloom as plants struggle in peak summer heat.

Companion Planting

Good Companions

Avoid Planting Near

  • Fennel

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Nasturtium in Swift Current, SK?

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

What planting zone is Swift Current, SK?

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

🌱

Your Swift Current Garden Planner — Free

A 22-page printable planner built for Swift Current (Zone 4a). 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 Swift Current, SK. Local conditions may vary. Last updated: June 2026.

Sources & credits

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