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When to plant Celosia in Jefferson County, MO

In Zone 6b (Jefferson County), direct-sow Celosia between April 17 and May 8 for spring, after the April 10 last-frost mark.

When to Plant Celosia in Jefferson County, MO

Celosia (Celosia argentea) encompasses the vivid cockscomb (cristata) and feathery plumed (plumosa) types that explode with color in summer heat. Drought-tolerant and disease-resistant, they thrive in the hottest parts of the season and produce long-lasting blooms both in the garden and as cut or dried flowers. A reliable filler in sunny annual beds.

Jefferson County, Missouri is in USDA Zone 6b. The average last spring frost is April 10 and the first fall frost is October 26, giving you a growing season of approximately 199 days.

At an elevation of 839 feet, Jefferson County receives approximately 33.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 87°F, providing good warmth for Celosia during the growing season.

Annual Blooms in Summer Pollinator-friendly Good for cutting
Jefferson County, MO (Zone 6b) Moderate season
199 days
Last Spring Frost April 10
199 growing days
First Fall Frost October 26

Jefferson County Soil Profile

Soil Type

Silt Loam

Soil pH

6.0-7.0

Drainage

Well Drained

Celosia Planting Timeline — Jefferson County, MO

Celosia Planting Calendar

Activity When Date Range
Start Indoors March 6 Mar 6 – Mar 20
Transplant Outdoors April 17 Apr 17 – May 1
Direct Sow April 17 Apr 17 – May 8
Bloom June 19 Jun 19 – Oct 9

Plant 0.1" deep · 9" apart · Rows 12" apart

Month-by-Month Timeline

MonthActivities
January
February
March Start Indoors
April Transplant Outdoors Direct Sow
May Transplant Outdoors Direct Sow
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 6–7 · Your soil: N/A

🗺️ USDA Zone

Zone 6b

📆 Growing Season

199 days in Jefferson County

Growing Tips for Jefferson County

Start seeds indoors 4–6 weeks before last frost, or direct-sow after soil warms above 60°F. Does not transplant well from large pots — sow in small cells or direct-sow. Needs full sun and warm soil; cold stress causes stunting. Pinch first bloom to encourage branching. Water at the base; wet foliage encourages fungal issues. Excellent dried flower — harvest before seeds set for the best color retention.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Celosia in Jefferson County, MO?

Jefferson County is in Zone 6b with an average last frost of April 10. Plan your Celosia planting based on this frost date — see the calendar above for exact timing.

What planting zone is Jefferson County, MO?

Jefferson County, Missouri is in USDA Hardiness Zone 6b. The average last spring frost is April 10 and first fall frost is October 26.

When should I plant Celosia in Jefferson County, MO?

In Jefferson County, MO, plant Celosia after the last frost (around April 10) and before the first frost (around October 26). Best results when soil holds above 50°F.

What growing zone is Jefferson County, MO for Celosia?

Jefferson County sits in USDA Zone 6b. Celosia grows reliably in zones 3a through 11b, so it's a good fit here.

Can Celosia grow in Jefferson County's climate?

Yes — Celosia grows well in Jefferson County's temperate climate. Jefferson County averages a 199-day frost-free season, with last frost around April 10 and first frost around October 26.

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Your Jefferson County Garden Planner — Free

A 22-page printable planner built for Jefferson County (Zone 6b). 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 Jefferson County, MO. Local conditions may vary. Last updated: July 2026.

Sources & credits

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