When to Plant Cumin in Larimer County, CO
Your May game plan for Larimer County, Colorado
May is a pivotal month for Larimer County, Colorado gardens. Focus on these tasks first and you'll set up the rest of the season for success.
Coming up in June — start thinking about
- Starting indoors: cumin
Cumin is a warm-season annual herb whose seeds are one of the most widely used spices globally. It requires a long, hot growing season of 3-4 months.
Larimer County, Colorado is in USDA Zone 5b. The average last spring frost is May 2 and the first fall frost is October 6, giving you a growing season of approximately 157 days.
At an elevation of 7,108 feet, Larimer County receives approximately 23.4 inches of rainfall annually with predominantly loam soil. Summer highs average 84°F, so choose short-season varieties of Cumin to ensure they mature before fall.
Larimer County Soil Profile
Soil Type
Loam
Soil pH
6.4-8.2
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 Larimer County
How your county's soil matches Cumin's growing requirements.
Soil pH
Your soil pH (6.4–8.2) overlaps with Cumin's range (6.0–8.0), though not a perfect match.
Soil Texture
The loam soil in Larimer County is excellent for Cumin — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Cumin.
Organic Matter
Organic matter is moderate (2.3%). Annual compost additions will help Cumin.
How to Plant Cumin
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Plant Water Budget
Water stress score is 8/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Cumin
Cumin needs approximately 0.5 inches of water per week (2.2" per month). Here's how your county's rainfall compares month by month.
| Month | Cumin Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.7" | 0" | ❄️ Dormant |
| Feb | — | 1.3" | 0" | ❄️ Dormant |
| Mar | — | 2.1" | 0" | ❄️ Dormant |
| Apr | — | 2.2" | 0" | ❄️ Dormant |
| May | 2.2" | 2.5" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 1.9" | 0.3" | 💧 Light watering |
| Jul | 2.2" | 2.3" | 0" | ✅ Rainfall sufficient |
| Aug | 2.2" | 2.5" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 2" | 0.2" | 💧 Light watering |
| Oct | 2.2" | 1.9" | 0.3" | 💧 Light watering |
| Nov | — | 1.7" | 0" | ❄️ Dormant |
| Dec | — | 1.3" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Oct in Larimer County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Cumin 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.
Cumin Planting Timeline — Larimer County, CO
Cumin Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 28 | Mar 28 – Apr 11 |
| Transplant Outdoors | April 25 | Apr 25 – May 9 |
| Direct Sow | April 18 | Apr 18 – May 9 |
| Harvest | August 8 | Aug 8 – Oct 10 |
| Fall Sowing | July 28 | Jul 28 – Aug 11 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Start Indoors Transplant Outdoors Direct Sow |
| May | Transplant Outdoors Direct Sow |
| June | — |
| July | Fall Sowing |
| August | Fall Sowing Harvest |
| September | Harvest |
| October | Harvest |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.5"/week · Only during dry spells
📅 Days to Maturity
100–120 days
🧪 Soil pH
Needs 6–8 · Your soil: acceptable
🗺️ USDA Zone
Zone 5b
📆 Growing Season
157 days in Larimer County
Growing Tips for Cumin in Larimer County
Direct sow Cumin outdoors after May 02 in Larimer County when soil has warmed and frost danger has passed.
Common pests for Cumin in this region include carrot rust fly and parsleyworm. Use row covers early in the season and inspect plants weekly.
Larimer County receives only 23" of rain annually. Cumin needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.
General growing tips
Start seeds indoors 4 weeks before last frost. Transplant after all danger of frost. Harvest when seed heads turn brown. Requires consistent warmth for proper seed development.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Cumin in Other Locations
Frequently Asked Questions
When should I plant Cumin in Larimer County, CO?
Larimer County is in Zone 5b with an average last frost of May 2. Plan your Cumin planting based on this frost date — see the calendar above for exact timing.
What planting zone is Larimer County, CO?
Larimer County, Colorado is in USDA Hardiness Zone 5b. The average last spring frost is May 2 and first fall frost is October 6.
Your Larimer County Garden Planner — Free
A 24-page printable planner built for Larimer 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.