When to Plant Black Beans in Gallatin County, MT
Black beans are a warm-season legume producing small, dark, protein-rich beans that are a staple in Latin American and Caribbean cuisines.
Gallatin County, Montana is in USDA Zone 4b. The average last spring frost is June 8 and the first fall frost is September 19, giving you a growing season of approximately 103 days.
At an elevation of 8,376 feet, Gallatin County receives approximately 12.4 inches of rainfall annually with predominantly loam soil. Summer highs average 82°F, so choose short-season varieties of Black Beans to ensure they mature before fall. With low rainfall, drip irrigation is essential for growing Black Beans successfully. Mulch heavily to conserve soil moisture.
Gallatin County Soil Profile
Soil Type
Loam
Soil pH
6.2-8.1
Drainage
Well Drained
Plant 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 Gallatin County
How your county's soil matches Black Beans's growing requirements.
Soil pH
Your soil pH (6.2–8.1) overlaps with Black Beans's range (6.0–7.5), though not a perfect match.
Soil Texture
The loam soil in Gallatin County is excellent for Black Beans — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.4%). Annual compost additions will help Black Beans.
How to Plant Black Beans
Plant Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Black Beans
Black Beans needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Black Beans Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 0.8" | 0" | ❄️ Dormant |
| Feb | — | 0.8" | 0" | ❄️ Dormant |
| Mar | — | 1.1" | 0" | ❄️ Dormant |
| Apr | — | 1.3" | 0" | ❄️ Dormant |
| May | — | 1.3" | 0" | ❄️ Dormant |
| Jun | 4.3" | 0.8" | 3.5" | 🚿 Regular watering |
| Jul | 4.3" | 1" | 3.3" | 🚿 Regular watering |
| Aug | 4.3" | 1.5" | 2.8" | 🚿 Regular watering |
| Sep | 4.3" | 1" | 3.3" | 🚿 Regular watering |
| Oct | — | 1.1" | 0" | ❄️ Dormant |
| Nov | — | 1" | 0" | ❄️ Dormant |
| Dec | — | 0.8" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Jun–Sep in Gallatin County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Black Beans 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.
Black Beans Planting Timeline — Gallatin County, MT
Black Beans Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Direct Sow | June 22 | Jun 22 – Jul 13 |
| Harvest | September 21 | Sep 21 – Nov 9 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | — |
| May | — |
| June | Direct Sow |
| July | Direct Sow |
| August | — |
| September | Harvest |
| October | Harvest |
| November | Harvest |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1"/week · 1-2 times/week
📅 Days to Maturity
90–120 days
🧪 Soil pH
Needs 6–7.5 · Your soil: acceptable
🗺️ USDA Zone
Zone 4b
📆 Growing Season
103 days in Gallatin County
Growing Tips for Black Beans in Gallatin County
Direct sow Black Beans outdoors after June 08 in Gallatin County when soil has warmed and frost danger has passed.
Your 103.0-day growing season in Gallatin County is tight for Black Beans (90.0-120.0 days to maturity). Start indoors and choose early-maturing varieties.
Common pests for Black Beans in this region include bean beetles and aphids. Use row covers early in the season and inspect plants weekly.
Gallatin County receives only 12" of rain annually. Black Beans needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.
General growing tips
Direct sow after last frost. Provide support for climbing varieties. Allow pods to dry fully on the vine before harvesting. Thresh dried pods by hand or in a pillowcase.
Companion Planting
Good Companions
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Check more plant combinations with our Companion Planting Checker →
Black Beans in Other Locations
Frequently Asked Questions
When should I plant Black Beans in Gallatin County, MT?
Gallatin County is in Zone 4b with an average last frost of June 8. Plan your Black Beans planting based on this frost date — see the calendar above for exact timing.
What planting zone is Gallatin County, MT?
Gallatin County, Montana is in USDA Hardiness Zone 4b. The average last spring frost is June 8 and first fall frost is September 19.
Plan Your Garden with Confidence
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