When to Plant Hyssop in Warren County, IN
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.
Warren County, Indiana is in USDA Zone 5b. The average last spring frost is April 19 and the first fall frost is October 14, giving you a growing season of approximately 178 days.
At an elevation of 764 feet, Warren County receives approximately 40.9 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86°F, providing good warmth for Hyssop during the growing season.
Warren County Soil Profile
Soil Type
Silt Loam
Soil pH
5.9-7.1
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.
Plant Water Budget
Hyssop Planting Timeline — Warren County, IN
Hyssop Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | April 26 | Apr 26 – May 10 |
| Harvest | July 5 | Jul 5 – Sep 6 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Transplant Outdoors |
| May | Transplant Outdoors |
| June | — |
| July | Harvest |
| August | Harvest |
| September | Harvest |
| October | — |
| November | — |
| December | — |
Growing Conditions
Sun
Full Sun (6-8+ hours)
Water
Low — drought tolerant
Days to Maturity
70–90 days
Soil pH
6 – 8
USDA Zone
Zone 5b
Growing Season
178 days
Growing Tips for Warren 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
Level Up Your Garden
Hyssop in Other Locations
Frequently Asked Questions
When should I plant Hyssop in Warren County, IN?
Warren County is in Zone 5b with an average last frost of April 19. Plan your Hyssop planting based on this frost date — see the calendar above for exact timing.
What planting zone is Warren County, IN?
Warren County, Indiana is in USDA Hardiness Zone 5b. The average last spring frost is April 19 and first fall frost is October 14.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Warren County gardeners in Zone 5b organize planting dates, track what's growing, and never miss a planting window.
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