When to plant Geraniums in Routt County, CO
In Routt County, Geraniums is a single-season spring crop — there's no second fall window. Plant June 19–July 3 for an 70–100-day harvest, finishing well before the September 8 first frost.
When to Plant Geraniums in Routt County, CO
Geraniums (Pelargonium × hortorum) are tender perennials grown as warm-season annuals throughout North America. Prized for their bold flower clusters, long bloom period, and tolerance of summer heat when planted in well-drained soil, they anchor window boxes, containers, and bed borders from late spring until hard frost. Zones 9b–11b can overwinter plants in the ground.
Routt County, Colorado is in USDA Zone 5a. The average last spring frost is June 12 and the first fall frost is September 8, giving you a growing season of approximately 88 days.
At an elevation of 5,381 feet, Routt County receives approximately 24.5 inches of rainfall annually with predominantly loam soil. Summer highs average 83°F, so choose short-season varieties of Geraniums to ensure they mature before fall.
Routt County Soil Profile
Soil Type
Loam
Soil pH
6.0-7.0
Drainage
Well Drained
Geraniums Planting Timeline — Routt County, CO
Geraniums Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | April 3 | Apr 3 – Apr 17 |
| Transplant Outdoors | June 19 | Jun 19 – Jul 3 |
| Bloom | August 28 | Aug 28 – Nov 20 |
Plant 0.1" deep · 12" apart · Rows 14" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Start Indoors |
| May | — |
| June | Transplant Outdoors |
| July | Transplant Outdoors |
| August | Bloom |
| September | Bloom |
| October | Bloom |
| November | Bloom |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
Moderate — regular watering
📅 Days to Maturity
70–100 days
🧪 Soil pH
Needs 6–7 · Your soil: N/A
🗺️ USDA Zone
Zone 5a
📆 Growing Season
88 days in Routt County
Growing Tips for Routt County
Start seeds indoors 10–12 weeks before last frost — germination is slow and erratic without bottom heat (70–75°F). Transplant after frost danger passes. Geraniums rarely direct-sown; cuttings or transplants are the standard. Deadhead spent umbels weekly to maintain continuous bloom. Let soil dry slightly between waterings to prevent root rot. In zones 10–11 plants may be left in ground year-round or overwintered as houseplants.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Geraniums in Other Locations
Frequently Asked Questions
When should I plant Geraniums in Routt County, CO?
Routt County is in Zone 5a with an average last frost of June 12. Plan your Geraniums planting based on this frost date — see the calendar above for exact timing.
What planting zone is Routt County, CO?
Routt County, Colorado is in USDA Hardiness Zone 5a. The average last spring frost is June 12 and first fall frost is September 8.
When should I plant Geraniums in Routt County, CO?
In Routt County, CO, plant Geraniums after the last frost (around June 12) and before the first frost (around September 8). Best results when soil holds above 50°F.
What growing zone is Routt County, CO for Geraniums?
Routt County sits in USDA Zone 5a. Geraniums grows reliably in zones 2a through 11b, so it's a good fit here.
Can Geraniums grow in Routt County's climate?
Yes — Geraniums grows well in Routt County's temperate climate. Routt County averages a 88-day frost-free season, with last frost around June 12 and first frost around September 8.
Your Routt County Garden Planner — Free
A 22-page printable planner built for Routt County (Zone 5a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.