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When to plant Cosmos in Greeley County, KS

Cosmos planted in Greeley County between April 30 and May 21 matures in 60–90 days — well before the October 10 first frost.

When to Plant Cosmos in Greeley County, KS

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.

Greeley County, Kansas is in USDA Zone 6a. The average last spring frost is April 30 and the first fall frost is October 10, giving you a growing season of approximately 163 days.

At an elevation of 963 feet, Greeley County receives approximately 21.1 inches of rainfall annually with predominantly loam soil. Summer highs average 87°F, providing good warmth for Cosmos during the growing season.

Annual Blooms in Summer Pollinator-friendly Good for cutting
Greeley County, KS (Zone 6a) Moderate season
163 days
Last Spring Frost April 30
163 growing days
First Fall Frost October 10

Greeley County Soil Profile

Soil Type

Loam

Soil pH

6.2-7.2

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 1.4" 0" ❄️ Dormant
Feb 1.4" 0" ❄️ Dormant
Mar 2.1" 0" ❄️ Dormant
Apr 4.3" 2" 2.3" 🚿 Regular watering
May 4.3" 2.7" 1.6" 💧 Light watering
Jun 4.3" 1.4" 2.9" 🚿 Regular watering
Jul 4.3" 1.6" 2.7" 🚿 Regular watering
Aug 4.3" 2" 2.3" 🚿 Regular watering
Sep 4.3" 2" 2.3" 🚿 Regular watering
Oct 4.3" 1.7" 2.6" 🚿 Regular watering
Nov 1.7" 0" ❄️ Dormant
Dec 1.1" 0" ❄️ Dormant

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

Cosmos Planting Timeline — Greeley County, KS

Cosmos Planting Calendar

Activity When Date Range
Start Indoors April 2 Apr 2 – Apr 16
Transplant Outdoors April 30 Apr 30 – May 14
Direct Sow April 30 Apr 30 – May 21
Bloom July 9 Jul 9 – Oct 15

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

Month-by-Month Timeline

MonthActivities
January
February
March
April Start Indoors Transplant Outdoors Direct Sow
May Transplant Outdoors Direct Sow
June
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 6a

📆 Growing Season

163 days in Greeley County

Growing Tips for Greeley 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 Greeley County, KS?

Greeley County is in Zone 6a with an average last frost of April 30. Plan your Cosmos planting based on this frost date — see the calendar above for exact timing.

What planting zone is Greeley County, KS?

Greeley County, Kansas is in USDA Hardiness Zone 6a. The average last spring frost is April 30 and first fall frost is October 10.

When should I plant Cosmos in Greeley County, KS?

In Greeley County, KS, plant Cosmos after the last frost (around April 30) and before the first frost (around October 10). Best results when soil holds above 50°F.

What growing zone is Greeley County, KS for Cosmos?

Greeley County sits in USDA Zone 6a. Cosmos grows reliably in zones 2a through 11b, so it's a good fit here.

Can Cosmos grow in Greeley County's climate?

Yes — Cosmos grows well in Greeley County's temperate climate. Greeley County averages a 163-day frost-free season, with last frost around April 30 and first frost around October 10.

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Your Greeley County Garden Planner — Free

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

Sources & credits

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