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When to Plant Collard Greens in Latah County, ID

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.

Latah County, Idaho is in USDA Zone 5b. The average last spring frost is May 11 and the first fall frost is September 23, giving you a growing season of approximately 135 days.

At an elevation of 5,530 feet, Latah County receives approximately 14.8 inches of rainfall annually with predominantly loam soil. Summer highs average 86ยฐF, providing good warmth for Collard Greens during the growing season. With low rainfall, drip irrigation is essential for growing Collard Greens successfully. Mulch heavily to conserve soil moisture.

Latah County, ID (Zone 5b) Short season
135 days
Last Spring Frost May 11
135 growing days
First Fall Frost September 23

Latah County Soil Profile

Soil Type

Loam

Soil pH

6.7-8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (16 days to spare)
Start indoors: Mar 30 Transplant: May 4 🍅 Harvest: Jun 29 – Aug 31
Recommended (50%) ✓ Fits season (16 days to spare)
Start indoors: Apr 6 Transplant: May 11 🍅 Harvest: Jul 6 – Sep 7
Safe Start (90%) ✓ Fits season (13 days to spare)
Start indoors: May 1 Transplant: Jun 5 🍅 Harvest: Jul 31 – Oct 2

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

Plant needs
1.0″/week
Rainfall provides
0.5″/week
You supply
1.0″/week
Watering frequency 2-3 times/week
Season total 1,210 gal / 100 sq ft
Drought risk

Water stress score is 8/10 โ€” consider drought-tolerant varieties and mulching

Collard Greens needs ~942 GDD — county provides 1,957 GDD Excellent fit

Collard Greens Planting Timeline โ€” Latah County, ID

Collard Greens Planting Calendar

Activity When Date Range
Start Indoors April 6 Apr 6 โ€“ Apr 20
Transplant Outdoors May 11 May 11 โ€“ May 25
Direct Sow April 27 Apr 27 โ€“ May 18
Fall Sowing July 15 Jul 15 โ€“ Jul 29
Harvest July 6 Jul 6 โ€“ Sep 7

Plant 1" deep ยท 15" apart ยท Rows 24" apart

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March โ€”
April Start Indoors Direct Sow
May Transplant Outdoors Direct Sow
June โ€”
July Fall Sowing Harvest
August Harvest
September Harvest
October โ€”
November โ€”
December โ€”

Growing Conditions

Sun

Full Sun (6-8+ hours)

Water

Moderate โ€” regular watering

Days to Maturity

55โ€“75 days

Soil pH

6 โ€“ 7

USDA Zone

Zone 5b

Growing Season

135 days

Growing Tips for Latah County

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

  • Strawberries
  • Tomatoes

Level Up Your Garden

Frequently Asked Questions

When should I plant Collard Greens in Latah County, ID?

Latah County is in Zone 5b with an average last frost of May 11. Plan your Collard Greens planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Latah County, ID?

Latah County, Idaho is in USDA Hardiness Zone 5b. The average last spring frost is May 11 and first fall frost is September 23.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Latah County gardeners in Zone 5b organize planting dates, track what's growing, and never miss a planting window.

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Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Latah County, ID. Local conditions may vary. Last updated: April 2026.