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When to Plant Hyssop in Barnstable County, MA

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.

Barnstable County, Massachusetts is in USDA Zone 7a. The average last spring frost is April 18 and the first fall frost is October 24, giving you a growing season of approximately 189 days.

At an elevation of 518 feet, Barnstable County receives approximately 45.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 91ยฐF, providing good warmth for Hyssop during the growing season.

Barnstable County, MA (Zone 7a) Moderate season
189 days
Last Spring Frost April 18
189 growing days
First Fall Frost October 24

Barnstable County Soil Profile

Soil Type

Silt Loam

Soil pH

5-6.4

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (50 days to spare)
Transplant: Apr 17 🍅 Harvest: Jun 26 – Aug 28
Recommended (50%) ✓ Fits season (49 days to spare)
Transplant: Apr 25 🍅 Harvest: Jul 4 – Sep 5
Safe Start (90%) ✓ Fits season (43 days to spare)
Transplant: May 18 🍅 Harvest: Jul 27 – Sep 28

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

Plant needs
0.5″/week
Rainfall provides
1.0″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft
Hyssop needs ~1,460 GDD — county provides 3,449 GDD Excellent fit

Hyssop Planting Timeline โ€” Barnstable County, MA

Hyssop Planting Calendar

Activity When Date Range
Transplant Outdoors April 25 Apr 25 โ€“ May 9
Harvest July 4 Jul 4 โ€“ Sep 5

Plant 0.5" deep ยท 8" apart ยท Rows 12" apart

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March โ€”
April Transplant Outdoors
May Transplant Outdoors
June โ€”
July Harvest
August Harvest
September Harvest
October โ€”
November โ€”
December โ€”

Growing Conditions

Sun

Full Sun (6-8+ hours)

Water

Low โ€” drought tolerant

Days to Maturity

70โ€“90 days

Soil pH

6 โ€“ 8

USDA Zone

Zone 7a

Growing Season

189 days

Growing Tips for Barnstable 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

  • Radish

Level Up Your Garden

Frequently Asked Questions

When should I plant Hyssop in Barnstable County, MA?

Barnstable County is in Zone 7a with an average last frost of April 18. Plan your Hyssop planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Barnstable County, MA?

Barnstable County, Massachusetts is in USDA Hardiness Zone 7a. The average last spring frost is April 18 and first fall frost is October 24.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Barnstable County gardeners in Zone 7a organize planting dates, track what's growing, and never miss a planting window.

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Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Barnstable County, MA. Local conditions may vary. Last updated: April 2026.