Blog

When to Plant Mache in Douglas County, CO

Mache (corn salad) is a cold-hardy salad green with small, rounded, tender leaves and a mild, nutty flavor. It thrives in cool weather and even overwinters in many climates.

Douglas County, Colorado is in USDA Zone 5b. The average last spring frost is May 22 and the first fall frost is September 20, giving you a growing season of approximately 121 days.

At an elevation of 7,421 feet, Douglas County receives approximately 12.9 inches of rainfall annually with predominantly loam soil. Summer highs average 85ยฐF, providing good warmth for Mache during the growing season. With low rainfall, drip irrigation is essential for growing Mache successfully. Mulch heavily to conserve soil moisture.

Douglas County, CO (Zone 5b) Short season
121 days
Last Spring Frost May 22
121 growing days
First Fall Frost September 20

Douglas County Soil Profile

Soil Type

Loam

Soil pH

6.7-8.4

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (45 days to spare)
Start indoors: Apr 7 Transplant: May 12 🍅 Harvest: Jun 23 – Jul 28
Recommended (50%) ✓ Fits season (44 days to spare)
Start indoors: Apr 17 Transplant: May 22 🍅 Harvest: Jul 3 – Aug 7
Safe Start (90%) ✓ Fits season (40 days to spare)
Start indoors: May 15 Transplant: Jun 19 🍅 Harvest: Jul 31 – Sep 4

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
0.7″/week
Watering frequency 1-2 times/week
Season total 714 gal / 100 sq ft
Drought risk

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

Mache needs ~688 GDD — county provides 1,663 GDD Excellent fit

Mache Planting Timeline โ€” Douglas County, CO

Mache Planting Calendar

Activity When Date Range
Start Indoors April 17 Apr 17 โ€“ May 1
Transplant Outdoors May 22 May 22 โ€“ Jun 5
Direct Sow May 8 May 8 โ€“ May 29
Fall Sowing July 12 Jul 12 โ€“ Jul 26
Harvest July 3 Jul 3 โ€“ Aug 7

Plant 0.5" deep ยท 6" apart ยท Rows 12" apart

Month-by-Month Timeline

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

Growing Conditions

Sun

Partial Shade (3-6 hours)

Water

Moderate โ€” regular watering

Days to Maturity

40โ€“60 days

Soil pH

6 โ€“ 7.5

USDA Zone

Zone 5b

Growing Season

121 days

Growing Tips for Douglas County

Direct sow in early spring or late summer for fall and winter harvest. Seeds need light to germinate so press gently into soil surface. Harvest whole rosettes.

Companion Planting

Good Companions

Level Up Your Garden

Frequently Asked Questions

When should I plant Mache in Douglas County, CO?

Douglas County is in Zone 5b with an average last frost of May 22. Plan your Mache planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Douglas County, CO?

Douglas County, Colorado is in USDA Hardiness Zone 5b. The average last spring frost is May 22 and first fall frost is September 20.

๐ŸŒฑ

Plan Your Garden with Confidence

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

Get Your Free Garden Planner →

Free download. Plan your entire garden season in minutes.

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