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When to plant Cosmos in Sharp County County,

In Sharp County County, plant Cosmos in spring between March 19 and April 9, once soil temps hold above 50°F. Sharp County County's last frost averages March 26, so most warm-season crops establish quickly once soil holds above 60°F. For a fall crop, sow between and — roughly 90 days before the first frost on November 2.

When to Plant Cosmos in Sharp County, AR

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.

Sharp County, Arkansas is in USDA Zone 7b. The average last spring frost is March 26 and the first fall frost is November 2, giving you a growing season of approximately 221 days.

At an elevation of 674 feet, Sharp County receives approximately 50.1 inches of rainfall annually with predominantly silt loam soil. Summer highs average 88°F, providing good warmth for Cosmos during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Cosmos root diseases.

Annual Blooms in Summer Pollinator-friendly Good for cutting
Sharp County, AR (Zone 7b) Long season
221 days
Last Spring Frost March 26
221 growing days
First Fall Frost November 2

Sharp County Soil Profile

Soil Type

Silt Loam

Soil pH

5.3-7

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 3.8" 0" ❄️ Dormant
Feb 4.5" 0" ❄️ Dormant
Mar 4.3" 4.5" 0" ✅ Rainfall sufficient
Apr 4.3" 4.2" 0.1" 💧 Light watering
May 4.3" 3.8" 0.5" 💧 Light watering
Jun 4.3" 4.4" 0" ✅ Rainfall sufficient
Jul 4.3" 5.7" 0" ✅ Rainfall sufficient
Aug 4.3" 4.3" 0" ✅ Rainfall sufficient
Sep 4.3" 3.9" 0.4" 💧 Light watering
Oct 4.3" 2.8" 1.5" 💧 Light watering
Nov 4.3" 4.2" 0.1" 💧 Light watering
Dec 4.1" 0" ❄️ Dormant

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

Cosmos Planting Timeline — Sharp County, AR

Cosmos Planting Calendar

Activity When Date Range
Start Indoors February 26 Feb 26 – Mar 12
Transplant Outdoors March 19 Mar 19 – Apr 2
Direct Sow March 19 Mar 19 – Apr 9
Bloom May 28 May 28 – Oct 1

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

Month-by-Month Timeline

MonthActivities
January
February Start Indoors
March Start Indoors Transplant Outdoors Direct Sow
April Transplant Outdoors Direct Sow
May Bloom
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 7b

📆 Growing Season

221 days in Sharp County

Growing Tips for Sharp 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 Sharp County, AR?

Sharp County is in Zone 7b with an average last frost of March 26. Plan your Cosmos planting based on this frost date — see the calendar above for exact timing.

What planting zone is Sharp County, AR?

Sharp County, Arkansas is in USDA Hardiness Zone 7b. The average last spring frost is March 26 and first fall frost is November 2.

When should I plant Cosmos in Sharp County County, ?

In Sharp County County, , plant Cosmos after the last frost (around March 26) and before the first frost (around November 2). Best results when soil holds above 50°F.

What growing zone is Sharp County County, for Cosmos?

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

Can Cosmos grow in Sharp County County's climate?

Yes — Cosmos grows well in Sharp County County's temperate climate. Sharp County County averages a 221-day frost-free season, with last frost around March 26 and first frost around November 2.

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Your Sharp County Garden Planner — Free

A 22-page printable planner built for Sharp County (Zone 7b). 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 Sharp County, AR. Local conditions may vary. Last updated: June 2026.

Sources & credits

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