When to plant Collard Greens in Jefferson County County,
Jefferson County County sits in USDA Zone 5a. Plant Collard Greens between June 1 (after last frost on June 15) and June 22. A second sowing from June 29 to July 13 extends the harvest into fall.
When to Plant Collard Greens in Jefferson County, MT
June in Jefferson County, Montana — your action list
June rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in Jefferson County, Montana.
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Move collard greens into the garden
Pick a cloudy afternoon or evening to plant. Less transplant shock, and your seedlings will barely blink.
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Scatter collard greens into prepared beds
Keep the top inch of soil moist until germination — a gentle morning watering for 5–7 days does the job.
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Sow collard greens for an autumn harvest
Keep young seedlings shaded and moist in summer heat. A row of taller crops works as natural shade.
July prep starts now
- Starting indoors: collard greens
Collard greens are a heat-tolerant member of the cabbage family with large, sturdy leaves. They are a Southern staple and one of the most nutritious leafy greens.
Jefferson County, Montana is in USDA Zone 5a. The average last spring frost is June 15 and the first fall frost is September 7, giving you a growing season of approximately 84 days.
At an elevation of 7,214 feet, Jefferson County receives approximately 21.5 inches of rainfall annually with predominantly loam soil. Summer highs average 82°F, so choose short-season varieties of Collard Greens to ensure they mature before fall.
Jefferson County Soil Profile
Soil Type
Loam
Soil pH
6.4-7.9
Drainage
Well Drained
Collard Greens 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 Jefferson County
How your county's soil matches Collard Greens's growing requirements.
Soil pH
Your soil pH (6.4–7.9) is more alkaline than Collard Greens prefers (6.0–7.0). Add sulfur or peat moss to lower pH.
Soil Texture
The loam soil in Jefferson County is excellent for Collard Greens — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Collard Greens.
Organic Matter
Organic matter is moderate (2.5%). Annual compost additions will help Collard Greens.
How to Plant Collard Greens
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Collard Greens Water Budget
Water stress score is 8/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Collard Greens
Collard Greens needs approximately 0.8 inches of water per week (3.5" per month). Here's how your county's rainfall compares month by month.
| Month | Collard Greens Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.5" | 0" | ❄️ Dormant |
| Feb | — | 1.4" | 0" | ❄️ Dormant |
| Mar | — | 2" | 0" | ❄️ Dormant |
| Apr | — | 2" | 0" | ❄️ Dormant |
| May | — | 2.5" | 0" | ❄️ Dormant |
| Jun | 3.5" | 1.5" | 2" | 🚿 Regular watering |
| Jul | 3.5" | 2" | 1.5" | 💧 Light watering |
| Aug | 3.5" | 2" | 1.5" | 💧 Light watering |
| Sep | 3.5" | 2" | 1.5" | 💧 Light watering |
| Oct | — | 1.8" | 0" | ❄️ Dormant |
| Nov | — | 1.4" | 0" | ❄️ Dormant |
| Dec | — | 1.4" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Jun–Sep in Jefferson County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Collard Greens 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.
Collard Greens Planting Timeline — Jefferson County, MT
Collard Greens Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | May 11 | May 11 – May 25 |
| Transplant Outdoors | June 15 | Jun 15 – Jun 29 |
| Direct Sow | June 1 | Jun 1 – Jun 22 |
| Harvest | August 10 | Aug 10 – Oct 12 |
| Fall Sowing | June 29 | Jun 29 – Jul 13 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | — |
| May | Start Indoors |
| June | Transplant Outdoors Direct Sow Fall Sowing |
| July | Fall Sowing |
| August | Harvest |
| September | Harvest |
| October | Harvest |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.8"/week · Natural rainfall sufficient
📅 Days to Maturity
55–75 days
🧪 Soil pH
Needs 6–7 · Your soil: too_alkaline
🗺️ USDA Zone
Zone 5a
📆 Growing Season
84 days in Jefferson County
Growing Tips for Collard Greens in Jefferson County
Direct sow Collard Greens outdoors after June 15 in Jefferson County when soil has warmed and frost danger has passed.
Your 84.0-day growing season in Jefferson County is tight for Collard Greens (55.0-75.0 days to maturity). Start indoors and choose early-maturing varieties.
Common pests for Collard Greens in this region include cabbage worm and flea beetles. Use row covers early in the season and inspect plants weekly.
General growing tips
Start seeds indoors or direct sow 4-6 weeks before last frost. Harvest lower leaves first, leaving the growing tip intact. Flavor improves after exposure to frost.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Collard Greens in Other Locations
Frequently Asked Questions
When should I plant Collard Greens in Jefferson County, MT?
Jefferson County is in Zone 5a with an average last frost of June 15. Plan your Collard Greens planting based on this frost date — see the calendar above for exact timing.
What planting zone is Jefferson County, MT?
Jefferson County, Montana is in USDA Hardiness Zone 5a. The average last spring frost is June 15 and first fall frost is September 7.
When should I plant Collard Greens in Jefferson County County, ?
In Jefferson County County, , plant Collard Greens after the last frost (around June 15) and before the first frost (around September 7). Best results when soil holds above 50°F.
What growing zone is Jefferson County County, for Collard Greens?
Jefferson County County sits in USDA Zone 5a. Collard Greens grows reliably in zones 2a through 11b, so it's a good fit here.
Can Collard Greens grow in Jefferson County County's climate?
Yes — Collard Greens grows well in Jefferson County County's temperate climate. Jefferson County County averages a 84-day frost-free season, with last frost around June 15 and first frost around September 7.
Your Jefferson County Garden Planner — Free
A 22-page printable planner built for Jefferson County (Zone 5a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.