When to plant Hyssop in Custer County, CO
Custer County sits in cold Zone 5b. Plant Hyssop May 30–June 13 for the single annual harvest; the September 25 first frost closes the window.
When to Plant Hyssop in Custer County, CO
Hyssop is a semi-evergreen perennial herb with intense blue flower spikes that attract bees and butterflies. It has a minty, slightly bitter flavor used in liqueurs and teas.
Custer County, Colorado is in USDA Zone 5b. The average last spring frost is May 23 and the first fall frost is September 25, giving you a growing season of approximately 125 days.
At an elevation of 8,115 feet, Custer County receives approximately 18.1 inches of rainfall annually with predominantly loam soil. Summer highs average 86°F, providing good warmth for Hyssop during the growing season. With low rainfall, drip irrigation is essential for growing Hyssop successfully. Mulch heavily to conserve soil moisture.
Custer County Soil Profile
Soil Type
Loam
Soil pH
6.0-7.0
Drainage
Well Drained
Hyssop Planting Timeline — Custer County, CO
Hyssop Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | May 30 | May 30 – Jun 13 |
| Harvest | August 8 | Aug 8 – Oct 10 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | — |
| May | Transplant Outdoors |
| June | Transplant Outdoors |
| July | — |
| August | Harvest |
| September | Harvest |
| October | Harvest |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
Low — drought tolerant
📅 Days to Maturity
70–90 days
🧪 Soil pH
Needs 6–8 · Your soil: N/A
🗺️ USDA Zone
Zone 5b
📆 Growing Season
125 days in Custer County
Growing Tips for Custer County
Start seeds indoors or direct sow in spring. Prune back in early spring to encourage bushy growth. Hyssop is drought-tolerant once established and thrives in poor soil.
Companion Planting
Good Companions
Avoid Planting Near
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Hyssop in Other Locations
Frequently Asked Questions
When should I plant Hyssop in Custer County, CO?
Custer County is in Zone 5b with an average last frost of May 23. Plan your Hyssop planting based on this frost date — see the calendar above for exact timing.
What planting zone is Custer County, CO?
Custer County, Colorado is in USDA Hardiness Zone 5b. The average last spring frost is May 23 and first fall frost is September 25.
When should I plant Hyssop in Custer County, CO?
In Custer County, CO, plant Hyssop after the last frost (around May 23) and before the first frost (around September 25). Best results when soil holds above 50°F.
What growing zone is Custer County, CO for Hyssop?
Custer County sits in USDA Zone 5b. Hyssop grows reliably in zones 3a through 9b, so it's a good fit here.
Can Hyssop grow in Custer County's climate?
Yes — Hyssop grows well in Custer County's temperate climate. Custer County averages a 125-day frost-free season, with last frost around May 23 and first frost around September 25.
Your Custer County Garden Planner — Free
A 22-page printable planner built for Custer 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.