When to plant Calendula in Garfield County, CO
Garfield County's 119-day season only supports one Calendula planting per year. Sow between April 27 and May 18 for the best chance at full maturity before September 21.
When to Plant Calendula in Garfield County, CO
This month in Garfield County, Colorado
July is a pivotal month for Garfield County, Colorado gardens. Focus on these tasks first and you'll set up the rest of the season for success.
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Sow calendula in trays indoors
You're about 11 weeks out from your last frost — the perfect window to get these germinating indoors.
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Pick calendula
Don't tug. Use scissors or pruners for clean cuts — torn stems invite disease.
Before August arrives, get these ready
- First harvests: calendula
Calendula (Calendula officinalis) is a cheerful, edible-flowered cool-season annual valued by herbalists, chefs, and gardeners alike. Its golden-orange petals are used in salves, teas, and as a saffron substitute. Hardy enough to tolerate light frosts, it blooms prolifically in spring and fall, taking a pause during the hottest weeks of summer.
Garfield County, Colorado is in USDA Zone 6a. The average last spring frost is May 25 and the first fall frost is September 21, giving you a growing season of approximately 119 days.
At an elevation of 7,997 feet, Garfield County receives approximately 21.3 inches of rainfall annually with predominantly loam soil. Summer highs average 84°F, so choose short-season varieties of Calendula to ensure they mature before fall.
Garfield County Soil Profile
Soil Type
Loam
Soil pH
6.5-7.9
Drainage
Well Drained
Calendula 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 Garfield County
How your county's soil matches Calendula's growing requirements.
Soil pH
Your soil pH (6.5–7.9) is more alkaline than Calendula prefers (5.5–7.0). Add sulfur or peat moss to lower pH.
Soil Texture
The loam soil in Garfield County is excellent for Calendula — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.8%). Annual compost additions will help Calendula.
How to Plant Calendula
Succession Planting Calendula
Sow every 5.7 weeks. Last sowing by Jul 13 to harvest before frost.
Calendula Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Calendula
Calendula 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 | Calendula Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.5" | 0" | ❄️ Dormant |
| Feb | — | 1.3" | 0" | ❄️ Dormant |
| Mar | — | 1.6" | 0" | ❄️ Dormant |
| Apr | — | 2.5" | 0" | ❄️ Dormant |
| May | 2.2" | 2.6" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 1.4" | 0.8" | 💧 Light watering |
| Jul | 2.2" | 1.8" | 0.4" | 💧 Light watering |
| Aug | 2.2" | 2.2" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 1.8" | 0.4" | 💧 Light watering |
| Oct | — | 1.7" | 0" | ❄️ Dormant |
| Nov | — | 1.6" | 0" | ❄️ Dormant |
| Dec | — | 1.2" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Sep in Garfield County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Calendula 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.
Calendula Planting Timeline — Garfield County, CO
Calendula Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | April 13 | Apr 13 – Apr 27 |
| Transplant Outdoors | May 25 | May 25 – Jun 8 |
| Direct Sow | April 27 | Apr 27 – May 18 |
| Bloom | July 13 | Jul 13 – Oct 12 |
Plant 0.3" deep · 9" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Start Indoors Direct Sow |
| May | Transplant Outdoors Direct Sow |
| June | Transplant Outdoors |
| July | Bloom |
| August | Bloom |
| September | Bloom |
| October | Bloom |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.5"/week · Natural rainfall sufficient
📅 Days to Maturity
50–70 days
🧪 Soil pH
Needs 5.5–7 · Your soil: too_alkaline
🗺️ USDA Zone
Zone 6a
📆 Growing Season
119 days in Garfield County
Growing Tips for Calendula in Garfield County
Direct sow Calendula outdoors after May 25 in Garfield County when soil has warmed and frost danger has passed.
Common pests for Calendula in this region include aphids and slugs. Use row covers early in the season and inspect plants weekly.
Garfield County receives only 21" of rain annually. Calendula needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.
General growing tips
Direct-sow in early spring as soon as soil can be worked — seeds germinate in cool soil (50-65°F). In zones 7+, also sow in fall for winter/spring bloom. Deadhead consistently to extend bloom. Plants self-seed readily; save a few spent heads and allow them to drop. Harvest petals when flowers are fully open for best flavor and medicinal value.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Calendula in Other Locations
Frequently Asked Questions
When should I plant Calendula in Garfield County, CO?
Garfield County is in Zone 6a with an average last frost of May 25. Plan your Calendula planting based on this frost date — see the calendar above for exact timing.
What planting zone is Garfield County, CO?
Garfield County, Colorado is in USDA Hardiness Zone 6a. The average last spring frost is May 25 and first fall frost is September 21.
When should I plant Calendula in Garfield County, CO?
In Garfield County, CO, plant Calendula after the last frost (around May 25) and before the first frost (around September 21). Best results when soil holds above 50°F.
What growing zone is Garfield County, CO for Calendula?
Garfield County sits in USDA Zone 6a. Calendula grows reliably in zones 2a through 11b, so it's a good fit here.
Can Calendula grow in Garfield County's climate?
Yes — Calendula grows well in Garfield County's temperate climate. Garfield County averages a 119-day frost-free season, with last frost around May 25 and first frost around September 21.
Your Garfield County Garden Planner — Free
A 22-page printable planner built for Garfield County (Zone 6a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.