Blog

When to Plant Squash (Summer) in Teton County, MT

Teton County, Montana Zone 4b May

What to do in May

Your Teton County, Montana garden is entering a new phase. Here's what's on the schedule for May and why each task matters now.

Avg. last frost May 25
Avg. first frost September 16
Soil temp (4") 28°F
Watering High
Pest pressure Low
Daylight 14.9 hrs
June will be here before you know it — start on
  • Transplants going out: squash (summer)
  • Direct-sowing: squash (summer)

Instant PDF download. No spam, unsubscribe any time.

Summer squash includes zucchini, yellow crookneck, and pattypan varieties that are harvested young and tender. They are prolific producers in warm weather.

Teton County, Montana is in USDA Zone 4b. The average last spring frost is May 25 and the first fall frost is September 16, giving you a growing season of approximately 114 days.

At an elevation of 8,276 feet, Teton County receives approximately 15.1 inches of rainfall annually with predominantly loam soil. Summer highs average 84°F, so choose short-season varieties of Squash (Summer) to ensure they mature before fall. With low rainfall, drip irrigation is essential for growing Squash (Summer) successfully. Mulch heavily to conserve soil moisture.

Teton County, MT (Zone 4b) Short season
114 days
Last Spring Frost May 25
114 growing days
First Fall Frost September 16
Share this guide:

Teton County Soil Profile

Soil Type

Loam

Soil pH

6.6-7.6

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Start indoors: Apr 8 Transplant: Jun 10 🍅 Harvest: Jul 29 – Sep 30
Recommended (50%) ✗ May not fit
Start indoors: Apr 13 Transplant: Jun 15 🍅 Harvest: Aug 3 – Oct 5
Safe Start (90%) ✗ May not fit
Start indoors: Apr 30 Transplant: Jul 2 🍅 Harvest: Aug 20 – Oct 22

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 Teton County

How your county's soil matches Squash (Summer)'s growing requirements.

Soil pH

Your soil pH (6.6–7.6) overlaps with Squash (Summer)'s range (6.0–7.5), though not a perfect match.

Soil Texture

The loam soil in Teton County is excellent for Squash (Summer) — good drainage, moisture retention, and nutrient holding capacity.

Drainage

Drainage is adequate for Squash (Summer).

Organic Matter

Organic matter is moderate (2.2%). Annual compost additions will help Squash (Summer).

How to Plant Squash (Summer)

1"
Planting Depth
30"
Between Plants
42"
Between Rows

Succession Planting Squash (Summer)

2
successive plantings in your 114-day season

Sow every 5.1 weeks. Last sowing by Jul 13 to harvest before frost.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.6″/week
You supply
0.9″/week
Watering frequency 2-3 times/week
Season total 905 gal / 100 sq ft
Drought risk

Water stress score is 6/10 — consider drought-tolerant varieties and mulching

Monthly Watering Guide for Squash (Summer)

Squash (Summer) needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Squash (Summer) Needs Rainfall You Supplement Action
Jan 1.1" 0" ❄️ Dormant
Feb 0.8" 0" ❄️ Dormant
Mar 1.2" 0" ❄️ Dormant
Apr 1.5" 0" ❄️ Dormant
May 4.3" 1.7" 2.6" 🚿 Regular watering
Jun 4.3" 1.2" 3.1" 🚿 Regular watering
Jul 4.3" 1.4" 2.9" 🚿 Regular watering
Aug 4.3" 1.7" 2.6" 🚿 Regular watering
Sep 4.3" 1.3" 3" 🚿 Regular watering
Oct 1.3" 0" ❄️ Dormant
Nov 0.9" 0" ❄️ Dormant
Dec 0.9" 0" ❄️ Dormant

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

Squash (Summer) 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.

Squash (Summer) needs ~715 GDD — county provides 1,482 GDD Excellent fit

Squash (Summer) Planting Timeline — Teton County, MT

Squash (Summer) Planting Calendar

Activity When Date Range
Start Indoors April 13 Apr 13 – Apr 27
Transplant Outdoors June 15 Jun 15 – Jun 29
Direct Sow June 8 Jun 8 – Jun 29
Harvest August 3 Aug 3 – Oct 5

Plant 1" deep · 30" apart · Rows 42" apart

Month-by-Month Timeline

MonthActivities
January
February
March
April Start Indoors
May
June Transplant Outdoors Direct Sow
July
August Harvest
September Harvest
October Harvest
November
December
Share this guide:

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · 2-3 times/week

📅 Days to Maturity

45–65 days

🧪 Soil pH

Needs 6–7.5 · Your soil: acceptable

🗺️ USDA Zone

Zone 4b

📆 Growing Season

114 days in Teton County

Growing Tips for Squash (Summer) in Teton County

Direct sow Squash (Summer) outdoors after May 25 in Teton County when soil has warmed and frost danger has passed.

Common pests for Squash (Summer) in this region include squash vine borer and cucumber beetles. Use row covers early in the season and inspect plants weekly.

Teton County receives only 15" of rain annually. Squash (Summer) needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.

General growing tips

Direct sow after last frost on mounds. Harvest frequently when fruits are 6-8 inches for best texture. Check plants daily as they grow rapidly in summer heat.

Companion Planting

Good Companions

Avoid Planting Near

  • Potatoes

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Squash (Summer) in Teton County, MT?

Teton County is in Zone 4b with an average last frost of May 25. Plan your Squash (Summer) planting based on this frost date — see the calendar above for exact timing.

What planting zone is Teton County, MT?

Teton County, Montana is in USDA Hardiness Zone 4b. The average last spring frost is May 25 and first fall frost is September 16.

🌱

Your Teton County Garden Planner — Free

A 24-page printable planner built for Teton 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.

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 Teton County, MT. Local conditions may vary. Last updated: May 2026.

Sources & credits

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