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When to Plant Cosmos in Latimer County, OK

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.

Latimer County, Oklahoma is in USDA Zone 7b. The average last spring frost is April 5 and the first fall frost is October 31, giving you a growing season of approximately 209 days.

At an elevation of 773 feet, Latimer County receives approximately 33.6 inches of rainfall annually with predominantly loam soil. Summer highs average 89°F, providing good warmth for Cosmos during the growing season.

Annual Blooms in Summer Pollinator-friendly Good for cutting
Latimer County, OK (Zone 7b) Long season
209 days
Last Spring Frost April 5
209 growing days
First Fall Frost October 31

Latimer County Soil Profile

Soil Type

Loam

Soil pH

6.5-7.2

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 0.9" 0" ❄️ Dormant
Feb 1.2" 0" ❄️ Dormant
Mar 2.2" 0" ❄️ Dormant
Apr 4.3" 3.8" 0.5" 💧 Light watering
May 4.3" 5.6" 0" ✅ Rainfall sufficient
Jun 4.3" 4.7" 0" ✅ Rainfall sufficient
Jul 4.3" 4.6" 0" ✅ Rainfall sufficient
Aug 4.3" 3.5" 0.8" 💧 Light watering
Sep 4.3" 3" 1.3" 💧 Light watering
Oct 4.3" 2.2" 2.1" 💧 Light watering
Nov 1" 0" ❄️ Dormant
Dec 0.8" 0" ❄️ Dormant

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

Cosmos Planting Timeline — Latimer County, OK

Cosmos Planting Calendar

Activity When Date Range
Start Indoors March 8 Mar 8 – Mar 22
Transplant Outdoors March 29 Mar 29 – Apr 12
Direct Sow March 29 Mar 29 – Apr 19
Bloom June 7 Jun 7 – Oct 11

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

Month-by-Month Timeline

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

📆 Growing Season

209 days in Latimer County

Growing Tips for Latimer 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 Latimer County, OK?

Latimer County is in Zone 7b with an average last frost of April 5. Plan your Cosmos planting based on this frost date — see the calendar above for exact timing.

What planting zone is Latimer County, OK?

Latimer County, Oklahoma is in USDA Hardiness Zone 7b. The average last spring frost is April 5 and first fall frost is October 31.

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Your Latimer County Garden Planner — Free

A 22-page printable planner built for Latimer 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 Latimer County, OK. Local conditions may vary. Last updated: July 2026.

Sources & credits

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