When to plant Hyssop in Windham County, CT
Windham County's short 170-day growing season means one Hyssop planting between May 6 and May 20. No fall crop in Zone 6a.
When to Plant Hyssop in Windham County, CT
June in the garden — Windham County, Connecticut
Welcome to June in Zone 6a. These are the moves that will have the biggest impact on your growing season.
July will be here before you know it — start on
- First harvests: hyssop
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.
Windham County, Connecticut is in USDA Zone 6a. The average last spring frost is April 29 and the first fall frost is October 16, giving you a growing season of approximately 170 days.
At an elevation of 110 feet, Windham County receives approximately 41.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85°F, providing good warmth for Hyssop during the growing season.
Windham County Soil Profile
Soil Type
Silt Loam
Soil pH
5.1-6.7
Drainage
Well Drained
Hyssop 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 Windham County
How your county's soil matches Hyssop's growing requirements.
Soil pH
Your soil pH (5.1–6.7) is more acidic than Hyssop prefers (6.0–8.0). Add garden lime to raise pH.
Soil Texture
The silt loam soil in Windham County is excellent for Hyssop — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (3.0%). Annual compost additions will help Hyssop.
How to Plant Hyssop
Succession Planting Hyssop
Sow every 8 weeks. Last sowing by Jul 18 to harvest before frost.
Hyssop Water Budget
Monthly Watering Guide for Hyssop
Hyssop 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 | Hyssop Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 3.2" | 0" | ❄️ Dormant |
| Feb | — | 3" | 0" | ❄️ Dormant |
| Mar | — | 3.2" | 0" | ❄️ Dormant |
| Apr | 2.2" | 3.3" | 0" | ✅ Rainfall sufficient |
| May | 2.2" | 3.8" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 3.7" | 0" | ✅ Rainfall sufficient |
| Jul | 2.2" | 4.9" | 0" | ✅ Rainfall sufficient |
| Aug | 2.2" | 3.6" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 3.2" | 0" | ✅ Rainfall sufficient |
| Oct | 2.2" | 3.2" | 0" | ✅ Rainfall sufficient |
| Nov | — | 3.2" | 0" | ❄️ Dormant |
| Dec | — | 3.3" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Windham County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Hyssop 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.
Hyssop Planting Timeline — Windham County, CT
Hyssop Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | May 6 | May 6 – May 20 |
| Harvest | July 15 | Jul 15 – Sep 16 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | — |
| May | Transplant Outdoors |
| June | — |
| July | Harvest |
| August | Harvest |
| September | Harvest |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.5"/week · Natural rainfall sufficient
📅 Days to Maturity
70–90 days
🧪 Soil pH
Needs 6–8 · Your soil: too_acidic
🗺️ USDA Zone
Zone 6a
📆 Growing Season
170 days in Windham County
Growing Tips for Hyssop in Windham County
Direct sow Hyssop outdoors after April 29 in Windham County when soil has warmed and frost danger has passed.
General growing tips
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
Check more plant combinations with our Companion Planting Checker →
Hyssop in Other Locations
Frequently Asked Questions
When should I plant Hyssop in Windham County, CT?
Windham County is in Zone 6a with an average last frost of April 29. Plan your Hyssop planting based on this frost date — see the calendar above for exact timing.
What planting zone is Windham County, CT?
Windham County, Connecticut is in USDA Hardiness Zone 6a. The average last spring frost is April 29 and first fall frost is October 16.
When should I plant Hyssop in Windham County, CT?
In Windham County, CT, plant Hyssop after the last frost (around April 29) and before the first frost (around October 16). Best results when soil holds above 50°F.
What growing zone is Windham County, CT for Hyssop?
Windham County sits in USDA Zone 6a. Hyssop grows reliably in zones 3a through 9b, so it's a good fit here.
Can Hyssop grow in Windham County's climate?
Yes — Hyssop grows well in Windham County's temperate climate. Windham County averages a 170-day frost-free season, with last frost around April 29 and first frost around October 16.
Your Windham County Garden Planner — Free
A 22-page printable planner built for Windham 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.