When to plant Larkspur in Eagle County, CO
Eagle County's 83-day season only supports one Larkspur planting per year. Sow between May 19 and June 9 for the best chance at full maturity before September 7.
When to Plant Larkspur in Eagle County, CO
Your June gardening checklist
Your garden in Eagle County, Colorado is working on a schedule, even when you're not. Here's where you should be this June.
Get ahead of July
- First harvests: larkspur
Larkspur (Consolida ajacis) is a cool-season annual that produces tall, delicate spires of blue, purple, pink, and white flowers reminiscent of its perennial cousin, delphinium. Direct-sown into cold soil or fall-sown in mild-winter climates, it blooms in spring before going to seed as summer heat arrives. An excellent cut flower and cottage-garden staple.
Eagle County, Colorado is in USDA Zone 5b. The average last spring frost is June 16 and the first fall frost is September 7, giving you a growing season of approximately 83 days.
At an elevation of 7,116 feet, Eagle County receives approximately 24.5 inches of rainfall annually with predominantly loam soil. Summer highs average 81°F, so choose short-season varieties of Larkspur to ensure they mature before fall.
Eagle County Soil Profile
Soil Type
Loam
Soil pH
6.6-7.7
Drainage
Well Drained
Larkspur 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 Eagle County
How your county's soil matches Larkspur's growing requirements.
Soil pH
Your soil pH (6.6–7.7) is more alkaline than Larkspur prefers (6.0–7.0). Add sulfur or peat moss to lower pH.
Soil Texture
The loam soil in Eagle County is excellent for Larkspur — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.2%). Annual compost additions will help Larkspur.
How to Plant Larkspur
Larkspur Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Larkspur
Larkspur 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 | Larkspur Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.8" | 0" | ❄️ Dormant |
| Feb | — | 1.2" | 0" | ❄️ Dormant |
| Mar | — | 2.4" | 0" | ❄️ Dormant |
| Apr | — | 2.8" | 0" | ❄️ Dormant |
| May | — | 3.2" | 0" | ❄️ Dormant |
| Jun | 2.2" | 1.6" | 0.6" | 💧 Light watering |
| Jul | 2.2" | 2.1" | 0.1" | 💧 Light watering |
| Aug | 2.2" | 2.4" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 1.8" | 0.4" | 💧 Light watering |
| Oct | — | 2" | 0" | ❄️ Dormant |
| Nov | — | 1.6" | 0" | ❄️ Dormant |
| Dec | — | 1.5" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Jun–Sep in Eagle County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Larkspur 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.
Larkspur Planting Timeline — Eagle County, CO
Larkspur Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Direct Sow | May 19 | May 19 – Jun 9 |
| Bloom | July 28 | Jul 28 – Sep 22 |
Plant 0.1" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | — |
| May | Direct Sow |
| June | Direct Sow |
| July | Bloom |
| August | Bloom |
| September | Bloom |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.5"/week · Natural rainfall sufficient
📅 Days to Maturity
60–90 days
🧪 Soil pH
Needs 6–7 · Your soil: too_alkaline
🗺️ USDA Zone
Zone 5b
📆 Growing Season
83 days in Eagle County
Growing Tips for Larkspur in Eagle County
Direct sow Larkspur outdoors after June 16 in Eagle County when soil has warmed and frost danger has passed.
Your 83.0-day growing season in Eagle County is tight for Larkspur (60.0-90.0 days to maturity). Start indoors and choose early-maturing varieties.
Eagle County receives only 24" of rain annually. Larkspur needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.
General growing tips
Larkspur does not transplant well — direct-sow only. In cold climates (zones 2–6), sow directly in early spring as soon as soil can be worked, 4–6 weeks before last frost; cold soil improves germination. In zones 7–10, fall-sow 8–10 weeks before first frost for spring bloom. Press seeds lightly into soil; they need darkness to germinate — cover with 1/8–1/4 inch of soil. Thin to 6–12 inches to prevent powdery mildew. Allow seed pods to mature and self-sow for naturalized colonies. All parts are toxic if ingested.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Larkspur in Other Locations
Frequently Asked Questions
When should I plant Larkspur in Eagle County, CO?
Eagle County is in Zone 5b with an average last frost of June 16. Plan your Larkspur planting based on this frost date — see the calendar above for exact timing.
What planting zone is Eagle County, CO?
Eagle County, Colorado is in USDA Hardiness Zone 5b. The average last spring frost is June 16 and first fall frost is September 7.
When should I plant Larkspur in Eagle County, CO?
In Eagle County, CO, plant Larkspur after the last frost (around June 16) and before the first frost (around September 7). Best results when soil holds above 50°F.
What growing zone is Eagle County, CO for Larkspur?
Eagle County sits in USDA Zone 5b. Larkspur grows reliably in zones 2a through 10b, so it's a good fit here.
Can Larkspur grow in Eagle County's climate?
Yes — Larkspur grows well in Eagle County's temperate climate. Eagle County averages a 83-day frost-free season, with last frost around June 16 and first frost around September 7.
Your Eagle County Garden Planner — Free
A 22-page printable planner built for Eagle 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.