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When to plant Cosmos in Lyon County, KY

Lyon County's spring Cosmos window runs April 4 through April 25. most warm-season crops establish quickly once soil holds above 60°F.

When to Plant Cosmos in Lyon County, KY

Cosmos (Cosmos bipinnatus) is an airy, feathery-foliaged cottage garden annual from Mexico that thrives on neglect. It produces delicate daisy-like blooms in shades of pink, white, and magenta from midsummer until frost. Cosmos is a prolific self-sower — once established in a garden it often returns year after year without replanting. Excellent habitat plant for beneficial insects.

Lyon County, Kentucky is in USDA Zone 7a. The average last spring frost is April 4 and the first fall frost is November 1, giving you a growing season of approximately 211 days.

At an elevation of 2,809 feet, Lyon County receives approximately 46.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85°F, providing good warmth for Cosmos during the growing season.

Annual Blooms in Summer Pollinator-friendly Good for cutting
Lyon County, KY (Zone 7a) Long season
211 days
Last Spring Frost April 4
211 growing days
First Fall Frost November 1

Lyon County Soil Profile

Soil Type

Silt Loam

Soil pH

5.7-6.6

Drainage

Well Drained

Monthly Watering Guide for Cosmos

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

Month Cosmos Needs Rainfall You Supplement Action
Jan 4.3" 0" ❄️ Dormant
Feb 3.6" 0" ❄️ Dormant
Mar 4.7" 0" ❄️ Dormant
Apr 4.3" 4" 0.3" 💧 Light watering
May 4.3" 3.7" 0.6" 💧 Light watering
Jun 4.3" 3.8" 0.5" 💧 Light watering
Jul 4.3" 5.5" 0" ✅ Rainfall sufficient
Aug 4.3" 4" 0.3" 💧 Light watering
Sep 4.3" 3.8" 0.5" 💧 Light watering
Oct 4.3" 2.5" 1.8" 💧 Light watering
Nov 4.3" 3.4" 0.9" 💧 Light watering
Dec 3.4" 0" ❄️ Dormant

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

Cosmos Planting Timeline — Lyon County, KY

Cosmos Planting Calendar

Activity When Date Range
Start Indoors March 7 Mar 7 – Mar 21
Transplant Outdoors April 4 Apr 4 – Apr 18
Direct Sow April 4 Apr 4 – Apr 25
Bloom June 13 Jun 13 – Oct 3

Plant 0.3" deep · 12" apart · Rows 18" apart

Month-by-Month Timeline

MonthActivities
January
February
March Start Indoors
April Transplant Outdoors Direct Sow
May
June Bloom
July Bloom
August Bloom
September Bloom
October Bloom
November
December

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

Low — drought tolerant

📅 Days to Maturity

60–90 days

🧪 Soil pH

Needs 6–8 · Your soil: N/A

🗺️ USDA Zone

Zone 7a

📆 Growing Season

211 days in Lyon County

Growing Tips for Lyon County

Direct-sow after last frost; cosmos germinates readily at 65-80°F in 7-10 days. Avoid rich soil — excess fertility produces lush foliage at the expense of blooms. Cosmos tolerates poor, dry soil exceptionally well. Pinch seedlings at 8 inches to encourage branching. Self-sows freely; allow some seed heads to mature and drop for a no-fuss perennial effect in warm climates.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Cosmos in Lyon County, KY?

Lyon County is in Zone 7a with an average last frost of April 4. Plan your Cosmos planting based on this frost date — see the calendar above for exact timing.

What planting zone is Lyon County, KY?

Lyon County, Kentucky is in USDA Hardiness Zone 7a. The average last spring frost is April 4 and first fall frost is November 1.

When should I plant Cosmos in Lyon County, KY?

In Lyon County, KY, plant Cosmos after the last frost (around April 4) and before the first frost (around November 1). Best results when soil holds above 50°F.

What growing zone is Lyon County, KY for Cosmos?

Lyon County sits in USDA Zone 7a. Cosmos grows reliably in zones 2a through 11b, so it's a good fit here.

Can Cosmos grow in Lyon County's climate?

Yes — Cosmos grows well in Lyon County's temperate climate. Lyon County averages a 211-day frost-free season, with last frost around April 4 and first frost around November 1.

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Your Lyon County Garden Planner — Free

A 22-page printable planner built for Lyon 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 Lyon County, KY. Local conditions may vary. Last updated: June 2026.

Sources & credits

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