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When to plant Crocus in Douglas County County,

The best window to plant Crocus in Douglas County County, is mid-spring–late spring, when soil warms to 50°F. Last frost typically hits May 22; first frost September 20. A second sowing from August 9 to August 23 extends the harvest into fall.

When to Plant Crocus in Douglas County, CO

Crocuses (Crocus spp.) are the heralds of spring — small, gem-like blooms that push up through frozen ground or even snow, often weeks before any other flower. Their compact corms naturalize readily in lawns, rock gardens, and borders, creating drifts of purple, white, and yellow that expand year after year. Bees prize early crocus as one of their first nectar and pollen sources of the season. The saffron crocus (C. sativus) blooms in fall and yields the world's most expensive spice.

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 85°F, providing good warmth for Crocus during the growing season. With low rainfall, drip irrigation is essential for growing Crocus successfully. Mulch heavily to conserve soil moisture.

Bulb Blooms in Spring Pollinator-friendly Fragrant
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

Monthly Watering Guide for Crocus

Crocus needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Crocus Needs Rainfall You Supplement Action
Jan 1" 0" ❄️ Dormant
Feb 0.8" 0" ❄️ Dormant
Mar 1.1" 0" ❄️ Dormant
Apr 1.3" 0" ❄️ Dormant
May 4.3" 1.4" 2.9" 🚿 Regular watering
Jun 4.3" 1" 3.3" 🚿 Regular watering
Jul 4.3" 1" 3.3" 🚿 Regular watering
Aug 4.3" 1.4" 2.9" 🚿 Regular watering
Sep 4.3" 1.1" 3.2" 🚿 Regular watering
Oct 1.1" 0" ❄️ Dormant
Nov 1" 0" ❄️ Dormant
Dec 0.8" 0" ❄️ Dormant

Water needs are for active growing months only (May–Sep in Douglas County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Crocus Planting Timeline — Douglas County, CO

Crocus Planting Calendar

Activity When Date Range
Bloom June 21 Jun 21 – Jul 12
Fall Sowing August 9 Aug 9 – Aug 23

Plant 4" deep · 3" apart · Rows 4" apart

Month-by-Month Timeline

MonthActivities
January
February
March
April
May
June Bloom
July Bloom
August Fall Sowing
September
October
November
December

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

Low — drought tolerant

📅 Days to Maturity

10–20 days

🧪 Soil pH

Needs 6–7 · Your soil: N/A

🗺️ USDA Zone

Zone 5b

📆 Growing Season

121 days in Douglas County

Growing Tips for Douglas County

Plant corms 3–4 inches deep and 2–3 inches apart in fall, when soil temperature drops below 60°F. Mass plantings (at least 25 corms per cluster) create the most visual impact. Plant in well-drained soil — corms rot in standing water. Crocus naturalize well under deciduous trees; the tree leafs out after crocus dormancy begins, so light competition is minimal. Squirrels and chipmunks dig corms — plant deeper (4 inches) or use wire mesh baskets in high-predation areas. Allow foliage to die back naturally before mowing lawns. In zones 8a–8b, plant in December with pre-chilled corms for best results.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Crocus in Douglas County, CO?

Douglas County is in Zone 5b with an average last frost of May 22. Plan your Crocus planting based on this frost date — 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.

When should I plant Crocus in Douglas County County, ?

In Douglas County County, , plant Crocus after the last frost (around May 22) and before the first frost (around September 20). Best results when soil holds above 50°F.

What growing zone is Douglas County County, for Crocus?

Douglas County County sits in USDA Zone 5b. Crocus grows reliably in zones 3a through 8b, so it's a good fit here.

Can Crocus grow in Douglas County County's climate?

Yes — Crocus grows well in Douglas County County's temperate climate. Douglas County County averages a 121-day frost-free season, with last frost around May 22 and first frost around September 20.

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Your Douglas County Garden Planner — Free

A 22-page printable planner built for Douglas County (Zone 5b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

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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 Douglas County, CO. Local conditions may vary. Last updated: June 2026.

Sources & credits

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