When to Plant Broccoli in Madison County, MT
Broccoli is a nutrient-dense cool-season crop that produces large central heads followed by smaller side shoots. It is one of the most popular garden vegetables.
Madison County, Montana is in USDA Zone 4a. The average last spring frost is June 11 and the first fall frost is September 13, giving you a growing season of approximately 94 days.
At an elevation of 6,394 feet, Madison County receives approximately 20.7 inches of rainfall annually with predominantly loam soil. Summer highs average 80°F, so choose short-season varieties of Broccoli to ensure they mature before fall.
Madison County Soil Profile
Soil Type
Loam
Soil pH
6.6-8.1
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.
Plant Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Broccoli Planting Timeline — Madison County, MT
Broccoli Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | April 30 | Apr 30 – May 14 |
| Transplant Outdoors | June 11 | Jun 11 – Jun 25 |
| Direct Sow | June 4 | Jun 4 – Jun 25 |
| Fall Sowing | June 21 | Jun 21 – Jul 5 |
| Harvest | August 13 | Aug 13 – Sep 24 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Start Indoors |
| May | Start Indoors |
| June | Transplant Outdoors Direct Sow Fall Sowing |
| July | Fall Sowing |
| August | Harvest |
| September | Harvest |
| October | — |
| November | — |
| December | — |
Growing Conditions
Sun
Full Sun (6-8+ hours)
Water
Moderate — regular watering
Days to Maturity
60–90 days
Soil pH
6 – 7
USDA Zone
Zone 4a
Growing Season
94 days
Growing Tips for Madison County
Start seeds indoors 6-8 weeks before last frost. Provide consistent moisture to prevent hollow stems. Harvest heads before yellow flowers appear.
Companion Planting
Good Companions
Avoid Planting Near
Level Up Your Garden
Isolate 1/2 mile from other brassicas. Biennial — must overwinter roots.
Broccoli in Other Locations
Frequently Asked Questions
When should I plant Broccoli in Madison County, MT?
Madison County is in Zone 4a with an average last frost of June 11. Plan your Broccoli planting based on this frost date — see the calendar above for exact timing.
What planting zone is Madison County, MT?
Madison County, Montana is in USDA Hardiness Zone 4a. The average last spring frost is June 11 and first fall frost is September 13.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Madison County gardeners in Zone 4a organize planting dates, track what's growing, and never miss a planting window.
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