When to plant Nasturtium in Garfield County County,
Plant Nasturtium in Garfield County County during the brief May 23–June 13 window. With 128 frost-free days, fall plantings can't mature before September 21.
When to Plant Nasturtium in Garfield County, MT
Top priorities for Garfield County, Montana gardeners in June
Your Garfield County, Montana garden is entering a new phase. Here's what's on the schedule for June and why each task matters now.
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Start nasturtium under lights
Bottom-water once the first true leaves appear — it keeps stems dry and knocks back damping-off.
Get ahead of July
- First harvests: nasturtium
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.
Garfield County, Montana is in USDA Zone 4b. The average last spring frost is May 16 and the first fall frost is September 21, giving you a growing season of approximately 128 days.
At an elevation of 8,464 feet, Garfield County receives approximately 18.8 inches of rainfall annually with predominantly loam soil. Summer highs average 81°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.
Garfield County Soil Profile
Soil Type
Loam
Soil pH
6.3-7.9
Drainage
Well Drained
Nasturtium Planting Risk Windows
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.
Soil Compatibility in Garfield County
How your county's soil matches Nasturtium's growing requirements.
Soil pH
Your soil pH (6.3–7.9) is within Nasturtium's preferred range (6.0–8.0).
Soil Texture
The loam soil in Garfield County is excellent for Nasturtium — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Nasturtium.
Organic Matter
Organic matter is moderate (2.5%). Annual compost additions will help Nasturtium.
How to Plant Nasturtium
Succession Planting Nasturtium
Sow every 6.3 weeks. Last sowing by Jul 18 to harvest before frost.
Nasturtium Water Budget
Water stress score is 8/10 — consider drought-tolerant varieties and mulching
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 | — | 1.2" | 0" | ❄️ Dormant |
| Feb | — | 1.2" | 0" | ❄️ Dormant |
| Mar | — | 1.7" | 0" | ❄️ Dormant |
| Apr | — | 1.7" | 0" | ❄️ Dormant |
| May | 2.2" | 2.3" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 1.4" | 0.8" | 💧 Light watering |
| Jul | 2.2" | 1.5" | 0.7" | 💧 Light watering |
| Aug | 2.2" | 2" | 0.2" | 💧 Light watering |
| Sep | 2.2" | 1.8" | 0.4" | 💧 Light watering |
| Oct | — | 1.5" | 0" | ❄️ Dormant |
| Nov | — | 1.4" | 0" | ❄️ Dormant |
| Dec | — | 1.1" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Sep in Garfield County). 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 Planting Timeline — Garfield County, MT
Nasturtium Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | April 18 | Apr 18 – May 2 |
| Transplant Outdoors | May 23 | May 23 – Jun 6 |
| Direct Sow | May 23 | May 23 – Jun 13 |
| Bloom | July 18 | Jul 18 – Oct 10 |
Plant 0.5" deep · 10" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| 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: ideal
🗺️ USDA Zone
Zone 4b
📆 Growing Season
128 days in Garfield County
Growing Tips for Nasturtium in Garfield County
Direct sow Nasturtium outdoors after May 16 in Garfield County when soil has warmed and frost danger has passed.
Garfield County receives only 19" 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
Check more plant combinations with our Companion Planting Checker →
Nasturtium in Other Locations
Frequently Asked Questions
When should I plant Nasturtium in Garfield County, MT?
Garfield County is in Zone 4b 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 Garfield County, MT?
Garfield County, Montana is in USDA Hardiness Zone 4b. The average last spring frost is May 16 and first fall frost is September 21.
When should I plant Nasturtium in Garfield County County, ?
In Garfield County County, , plant Nasturtium after the last frost (around May 16) and before the first frost (around September 21). Best results when soil holds above 50°F.
What growing zone is Garfield County County, for Nasturtium?
Garfield County County sits in USDA Zone 4b. Nasturtium grows reliably in zones 2a through 11b, so it's a good fit here.
Can Nasturtium grow in Garfield County County's climate?
Yes — Nasturtium grows well in Garfield County County's temperate climate. Garfield County County averages a 128-day frost-free season, with last frost around May 16 and first frost around September 21.
Your Garfield County Garden Planner — Free
A 22-page printable planner built for Garfield County (Zone 4b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.