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When to plant Hyssop in Johnson County, KS

In Johnson County, Hyssop is a single-season spring crop — there's no second fall window. Plant April 15–April 29 for an 70–90-day harvest, finishing well before the October 26 first frost.

When to Plant Hyssop in Johnson County, KS

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.

Johnson County, Kansas is in USDA Zone 6b. The average last spring frost is April 8 and the first fall frost is October 26, giving you a growing season of approximately 201 days.

At an elevation of 768 feet, Johnson County receives approximately 27.6 inches of rainfall annually with predominantly loam soil. Summer highs average 87°F, providing good warmth for Hyssop during the growing season.

Johnson County, KS (Zone 6b) Long season
201 days
Last Spring Frost April 8
201 growing days
First Fall Frost October 26

Johnson County Soil Profile

Soil Type

Loam

Soil pH

6.8-7.2

Drainage

Well Drained

Monthly Watering Guide for Hyssop

Hyssop needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Hyssop Needs Rainfall You Supplement Action
Jan 0.8" 0" ❄️ Dormant
Feb 0.8" 0" ❄️ Dormant
Mar 1.9" 0" ❄️ Dormant
Apr 4.3" 3.2" 1.1" 💧 Light watering
May 4.3" 3.7" 0.6" 💧 Light watering
Jun 4.3" 4.1" 0.2" 💧 Light watering
Jul 4.3" 3.8" 0.5" 💧 Light watering
Aug 4.3" 3.5" 0.8" 💧 Light watering
Sep 4.3" 2.3" 2" 💧 Light watering
Oct 4.3" 1.8" 2.5" 🚿 Regular watering
Nov 1" 0" ❄️ Dormant
Dec 0.7" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Johnson County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Hyssop Planting Timeline — Johnson County, KS

Hyssop Planting Calendar

Activity When Date Range
Transplant Outdoors April 15 Apr 15 – Apr 29
Harvest June 24 Jun 24 – Aug 26

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

Month-by-Month Timeline

MonthActivities
January
February
March
April Transplant Outdoors
May
June Harvest
July Harvest
August Harvest
September
October
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 6b

📆 Growing Season

201 days in Johnson County

Growing Tips for Johnson 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

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Hyssop in Johnson County, KS?

Johnson County is in Zone 6b with an average last frost of April 8. Plan your Hyssop planting based on this frost date — see the calendar above for exact timing.

What planting zone is Johnson County, KS?

Johnson County, Kansas is in USDA Hardiness Zone 6b. The average last spring frost is April 8 and first fall frost is October 26.

When should I plant Hyssop in Johnson County, KS?

In Johnson County, KS, plant Hyssop after the last frost (around April 8) and before the first frost (around October 26). Best results when soil holds above 50°F.

What growing zone is Johnson County, KS for Hyssop?

Johnson County sits in USDA Zone 6b. Hyssop grows reliably in zones 3a through 9b, so it's a good fit here.

Can Hyssop grow in Johnson County's climate?

Yes — Hyssop grows well in Johnson County's temperate climate. Johnson County averages a 201-day frost-free season, with last frost around April 8 and first frost around October 26.

🌱

Your Johnson County Garden Planner — Free

A 22-page printable planner built for Johnson County (Zone 6b). 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 Johnson County, KS. Local conditions may vary. Last updated: June 2026.

Sources & credits

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