When to Plant Kale in Douglas County, CO
Your May planting checklist for Douglas County, Colorado
Here's what deserves your attention in Douglas County, Colorado this month. Everything below is tailored to Zone 5b and timed around your local frost dates.
-
Plant out kale
Frost risk is low now in Douglas County, Colorado. If you've been covering beds overnight, you can stop.
-
Seed kale outdoors
Keep the top inch of soil moist until germination — a gentle morning watering for 5–7 days does the job.
Looking ahead to June
- Starting indoors: kale
Kale is an exceptionally hardy, nutrient-dense green available in curly, lacinato, and Russian varieties. It tolerates heavy frost and often tastes sweeter after cold exposure.
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 Kale during the growing season. With low rainfall, drip irrigation is essential for growing Kale successfully. Mulch heavily to conserve soil moisture.
Douglas County Soil Profile
Soil Type
Loam
Soil pH
6.7-8.4
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.
Soil Compatibility in Douglas County
How your county's soil matches Kale's growing requirements.
Soil pH
Your soil pH (6.7–8.4) is more alkaline than Kale prefers (6.0–7.5). Add sulfur or peat moss to lower pH.
Soil Texture
The loam soil in Douglas County is excellent for Kale — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.6%). Annual compost additions will help Kale.
How to Plant Kale
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Succession Planting Kale
Sow every 5.7 weeks. Last sowing by Jul 12 to harvest before frost.
For a dedicated fall crop, sow by Jul 12.
Plant Water Budget
Water stress score is 8/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Kale
Kale 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 | Kale 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 | 3.5" | 1.4" | 2.1" | 🚿 Regular watering |
| Jun | 3.5" | 1" | 2.5" | 🚿 Regular watering |
| Jul | 3.5" | 1" | 2.5" | 🚿 Regular watering |
| Aug | 3.5" | 1.4" | 2.1" | 🚿 Regular watering |
| Sep | 3.5" | 1.1" | 2.4" | 🚿 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.
Kale 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.
Kale Planting Timeline — Douglas County, CO
Kale Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | April 17 | Apr 17 – May 1 |
| Transplant Outdoors | May 22 | May 22 – Jun 5 |
| Direct Sow | May 8 | May 8 – May 29 |
| Harvest | July 17 | Jul 17 – Sep 11 |
| Fall Sowing | July 12 | Jul 12 – Jul 26 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Start Indoors |
| May | Start Indoors Transplant Outdoors Direct Sow |
| June | Transplant Outdoors |
| July | Fall Sowing Harvest |
| August | Harvest |
| September | Harvest |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.8"/week · 1-2 times/week
📅 Days to Maturity
50–70 days
🧪 Soil pH
Needs 6–7.5 · Your soil: too_alkaline
🗺️ USDA Zone
Zone 5b
📆 Growing Season
121 days in Douglas County
Growing Tips for Kale in Douglas County
Direct sow Kale outdoors after May 22 in Douglas County when soil has warmed and frost danger has passed.
Common pests for Kale in this region include cabbage worm and flea beetles. Use row covers early in the season and inspect plants weekly.
General growing tips
Direct sow or transplant in early spring or late summer. Harvest outer leaves first to keep plants productive. Kale overwinters in many climates and can provide greens all year.
Recommended Kale Varieties for Douglas County
Cold-hardy kale that improves in flavor after frost
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Isolate 1/2 mile from other brassicas (broccoli, cabbage, etc.) — they all cross.
Kale in Other Locations
Frequently Asked Questions
When should I plant Kale in Douglas County, CO?
Douglas County is in Zone 5b with an average last frost of May 22. Plan your Kale 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.
Your Douglas County Garden Planner — Free
A 24-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.