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When to plant Hyssop in Kossuth County, IA

Kossuth County sits in cold Zone 5a. Plant Hyssop May 4–May 18 for the single annual harvest; the October 6 first frost closes the window.

When to Plant Hyssop in Kossuth County, IA

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.

Kossuth County, Iowa is in USDA Zone 5a. The average last spring frost is April 27 and the first fall frost is October 6, giving you a growing season of approximately 162 days.

At an elevation of 1,213 feet, Kossuth County receives approximately 36.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 80°F, so choose short-season varieties of Hyssop to ensure they mature before fall.

Kossuth County, IA (Zone 5a) Moderate season
162 days
Last Spring Frost April 27
162 growing days
First Fall Frost October 6

Kossuth County Soil Profile

Soil Type

Silt Loam

Soil pH

6.0-7.0

Drainage

Well Drained

Hyssop Planting Timeline — Kossuth County, IA

Hyssop Planting Calendar

Activity When Date Range
Transplant Outdoors May 4 May 4 – May 18
Harvest July 13 Jul 13 – Sep 14

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

Month-by-Month Timeline

MonthActivities
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

Low — drought tolerant

📅 Days to Maturity

70–90 days

🧪 Soil pH

Needs 6–8 · Your soil: N/A

🗺️ USDA Zone

Zone 5a

📆 Growing Season

162 days in Kossuth County

Growing Tips for Kossuth 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 Kossuth County, IA?

Kossuth County is in Zone 5a with an average last frost of April 27. Plan your Hyssop planting based on this frost date — see the calendar above for exact timing.

What planting zone is Kossuth County, IA?

Kossuth County, Iowa is in USDA Hardiness Zone 5a. The average last spring frost is April 27 and first fall frost is October 6.

When should I plant Hyssop in Kossuth County, IA?

In Kossuth County, IA, plant Hyssop after the last frost (around April 27) and before the first frost (around October 6). Best results when soil holds above 50°F.

What growing zone is Kossuth County, IA for Hyssop?

Kossuth County sits in USDA Zone 5a. Hyssop grows reliably in zones 3a through 9b, so it's a good fit here.

Can Hyssop grow in Kossuth County's climate?

Yes — Hyssop grows well in Kossuth County's temperate climate. Kossuth County averages a 162-day frost-free season, with last frost around April 27 and first frost around October 6.

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A 22-page printable planner built for Kossuth County (Zone 5a). 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 Kossuth County, IA. Local conditions may vary. Last updated: June 2026.

Sources & credits

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