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When to plant Celosia in Floyd County, IA

For Celosia in Floyd County, the safe spring window opens around May 15 and closes around June 5. Last expected frost is May 1, first fall frost October 7, giving a 159-day growing season.

When to Plant Celosia in Floyd County, IA

Floyd County, Iowa Zone 5a June

Your June game plan for Floyd County, Iowa

A quick June briefing for Floyd County, Iowa gardeners — what's urgent, what's next, and what can wait.

Avg. last frost May 1
Avg. first frost October 7
Soil temp (4") 64°F
Watering Low
Pest pressure High
Daylight 15.2 hrs
  1. Time to start celosia inside

    You're about 15 weeks out from your last frost — the perfect window to get these germinating indoors.

July will be here before you know it — start on
  • First harvests: celosia

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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.

Floyd County, Iowa is in USDA Zone 5a. The average last spring frost is May 1 and the first fall frost is October 7, giving you a growing season of approximately 159 days.

At an elevation of 714 feet, Floyd County receives approximately 32.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 80°F, so choose short-season varieties of Celosia to ensure they mature before fall.

Annual Blooms in Summer Pollinator-friendly Good for cutting
Floyd County, IA (Zone 5a) Moderate season
159 days
Last Spring Frost May 1
159 growing days
First Fall Frost October 7

Floyd County Soil Profile

Soil Type

Silt Loam

Soil pH

5.9-6.8

Drainage

Well Drained

Celosia Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Start indoors: Mar 21 Transplant: May 9 🌸 Bloom: Jul 11 – Oct 10
Recommended (50%) ✗ May not fit
Start indoors: Mar 27 Transplant: May 15 🌸 Bloom: Jul 17 – Oct 16
Safe Start (90%) ✗ May not fit
Start indoors: Apr 10 Transplant: May 29 🌸 Bloom: Jul 31 – Oct 30

Percentages indicate frost risk at transplant. The 70% safe window means there is a 30% chance of frost after transplant — suitable for cold-hardy crops or gardeners with frost protection. The 90% safe window is best for tender plants.

Soil Compatibility in Floyd County

How your county's soil matches Celosia's growing requirements.

Soil pH

Your soil pH (5.9–6.8) overlaps with Celosia's range (6.0–7.0), though not a perfect match.

Soil Texture

The silt loam soil in Floyd County is excellent for Celosia — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (4.0%). Annual compost additions will help Celosia.

How to Plant Celosia

0.1"
Planting Depth
9"
Between Plants
12"
Between Rows

Succession Planting Celosia

3
successive plantings in your 159-day season

Sow every 6.9 weeks. Last sowing by Jul 09 to harvest before frost.

Celosia Water Budget

Plant needs
0.5″/week
Rainfall provides
0.9″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft

Monthly Watering Guide for Celosia

Celosia needs approximately 0.5 inches of water per week (2.2" per month). Here's how your county's rainfall compares month by month.

Month Celosia Needs Rainfall You Supplement Action
Jan 1.4" 0" ❄️ Dormant
Feb 1.4" 0" ❄️ Dormant
Mar 2.6" 0" ❄️ Dormant
Apr 3.1" 0" ❄️ Dormant
May 2.2" 3.6" 0" ✅ Rainfall sufficient
Jun 2.2" 3.8" 0" ✅ Rainfall sufficient
Jul 2.2" 3.9" 0" ✅ Rainfall sufficient
Aug 2.2" 3.4" 0" ✅ Rainfall sufficient
Sep 2.2" 3" 0" ✅ Rainfall sufficient
Oct 2.2" 2.9" 0" ✅ Rainfall sufficient
Nov 2.1" 0" ❄️ Dormant
Dec 1.6" 0" ❄️ Dormant

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

Celosia Heat Requirements (GDD)

What are Growing Degree Days (GDD)?

Growing Degree Days measure the total warmth your plants receive during the growing season. Think of it as a "heat bank" — every day above 50°F deposits warmth that helps your plants grow.

Each plant needs a certain amount of accumulated heat to mature. If your county provides more GDD than the plant needs, it's a great fit. If it's close, you may want to choose faster-maturing varieties or start seeds indoors to get a head start.

Celosia needs ~750 GDD — county provides 1,590 GDD Excellent fit

Celosia Planting Timeline — Floyd County, IA

Celosia Planting Calendar

Activity When Date Range
Start Indoors March 27 Mar 27 – Apr 10
Transplant Outdoors May 15 May 15 – May 29
Direct Sow May 15 May 15 – Jun 5
Bloom July 17 Jul 17 – Oct 16

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.5"/week · Natural rainfall sufficient

📅 Days to Maturity

60–90 days

🧪 Soil pH

Needs 6–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 5a

📆 Growing Season

159 days in Floyd County

Growing Tips for Celosia in Floyd County

Direct sow Celosia outdoors after May 01 in Floyd County when soil has warmed and frost danger has passed.

General growing tips

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 Floyd County, IA?

Floyd County is in Zone 5a with an average last frost of May 1. Plan your Celosia planting based on this frost date — see the calendar above for exact timing.

What planting zone is Floyd County, IA?

Floyd County, Iowa is in USDA Hardiness Zone 5a. The average last spring frost is May 1 and first fall frost is October 7.

When should I plant Celosia in Floyd County, IA?

In Floyd County, IA, plant Celosia after the last frost (around May 1) and before the first frost (around October 7). Best results when soil holds above 50°F.

What growing zone is Floyd County, IA for Celosia?

Floyd County sits in USDA Zone 5a. Celosia grows reliably in zones 3a through 11b, so it's a good fit here.

Can Celosia grow in Floyd County's climate?

Yes — Celosia grows well in Floyd County's temperate climate. Floyd County averages a 159-day frost-free season, with last frost around May 1 and first frost around October 7.

🌱

Your Floyd County Garden Planner — Free

A 22-page printable planner built for Floyd County (Zone 5a). 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 Floyd County, IA. Local conditions may vary. Last updated: June 2026.

Sources & credits

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