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When to Plant Hyssop in Cumberland County, KY

Cumberland County, Kentucky Zone 7a May

Your May planting checklist for Cumberland County, Kentucky

May is a pivotal month for Cumberland County, Kentucky gardens. Focus on these tasks first and you'll set up the rest of the season for success.

Avg. last frost April 13
Avg. first frost October 23
Soil temp (4") 55°F
Watering Moderate
Pest pressure Low
Daylight 14 hrs
Coming up in June — start thinking about
  • First harvests: hyssop

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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.

Cumberland County, Kentucky is in USDA Zone 7a. The average last spring frost is April 13 and the first fall frost is October 23, giving you a growing season of approximately 193 days.

At an elevation of 2,939 feet, Cumberland County receives approximately 52.2 inches of rainfall annually with predominantly silt loam soil. Summer highs average 87°F, providing good warmth for Hyssop during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Hyssop root diseases.

Cumberland County, KY (Zone 7a) Moderate season
193 days
Last Spring Frost April 13
193 growing days
First Fall Frost October 23

Cumberland County Soil Profile

Soil Type

Silt Loam

Soil pH

5.7-6.9

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (53 days to spare)
Transplant: Apr 14 🍅 Harvest: Jun 23 – Aug 25
Recommended (50%) ✓ Fits season (53 days to spare)
Transplant: Apr 20 🍅 Harvest: Jun 29 – Aug 31
Safe Start (90%) ✓ Fits season (45 days to spare)
Transplant: May 10 🍅 Harvest: Jul 19 – Sep 20

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 Cumberland County

How your county's soil matches Hyssop's growing requirements.

Soil pH

Your soil pH (5.7–6.9) overlaps with Hyssop's range (6.0–8.0), though not a perfect match.

Soil Texture

The silt loam soil in Cumberland County is excellent for Hyssop — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (3.1%). Annual compost additions will help Hyssop.

How to Plant Hyssop

0.5"
Planting Depth
8"
Between Plants
12"
Between Rows

Succession Planting Hyssop

3
successive plantings in your 193-day season

Sow every 8 weeks. Last sowing by Jul 25 to harvest before frost.

Plant Water Budget

Plant needs
0.5″/week
Rainfall provides
1.1″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft
Drought risk

Water stress score is 6/10 — consider drought-tolerant varieties and mulching

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 4.8" 0" ❄️ Dormant
Feb 4.4" 0" ❄️ Dormant
Mar 4.9" 0" ❄️ Dormant
Apr 2.2" 3.5" 0" ✅ Rainfall sufficient
May 2.2" 3.7" 0" ✅ Rainfall sufficient
Jun 2.2" 4.8" 0" ✅ Rainfall sufficient
Jul 2.2" 6.1" 0" ✅ Rainfall sufficient
Aug 2.2" 4.7" 0" ✅ Rainfall sufficient
Sep 2.2" 3.9" 0" ✅ Rainfall sufficient
Oct 2.2" 3.8" 0" ✅ Rainfall sufficient
Nov 4" 0" ❄️ Dormant
Dec 3.6" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Cumberland 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 needs ~1,220 GDD — county provides 2,943 GDD Excellent fit

Hyssop Planting Timeline — Cumberland County, KY

Hyssop Planting Calendar

Activity When Date Range
Transplant Outdoors April 20 Apr 20 – May 4
Harvest June 29 Jun 29 – Aug 31

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

Month-by-Month Timeline

MonthActivities
January
February
March
April Transplant Outdoors
May Transplant Outdoors
June Harvest
July Harvest
August Harvest
September
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: acceptable

🗺️ USDA Zone

Zone 7a

📆 Growing Season

193 days in Cumberland County

Growing Tips for Hyssop in Cumberland County

Direct sow Hyssop outdoors after April 13 in Cumberland 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

  • Radish

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Hyssop in Cumberland County, KY?

Cumberland County is in Zone 7a with an average last frost of April 13. Plan your Hyssop planting based on this frost date — see the calendar above for exact timing.

What planting zone is Cumberland County, KY?

Cumberland County, Kentucky is in USDA Hardiness Zone 7a. The average last spring frost is April 13 and first fall frost is October 23.

🌱

Your Cumberland County Garden Planner — Free

A 24-page printable planner built for Cumberland County (Zone 7a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

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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 Cumberland County, KY. Local conditions may vary. Last updated: May 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.