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When to Plant Sunflower in Ellis County, KS

Sunflowers are tall, cheerful annuals grown for their edible seeds and as pollinator magnets. They come in sizes from 2-foot dwarfs to 12-foot giants.

Ellis County, Kansas is in USDA Zone 6a. The average last spring frost is April 24 and the first fall frost is October 15, giving you a growing season of approximately 174 days.

At an elevation of 664 feet, Ellis County receives approximately 20.2 inches of rainfall annually with predominantly loam soil. Summer highs average 90ยฐF, providing good warmth for Sunflower during the growing season.

Ellis County, KS (Zone 6a) Moderate season
174 days
Last Spring Frost April 24
174 growing days
First Fall Frost October 15

Ellis County Soil Profile

Soil Type

Loam

Soil pH

6.5-7.2

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (41 days to spare)
Start indoors: Feb 20 Transplant: May 1 🍅 Harvest: Jul 10 – Aug 28
Recommended (50%) ✓ Fits season (41 days to spare)
Start indoors: Feb 27 Transplant: May 8 🍅 Harvest: Jul 17 – Sep 4
Safe Start (90%) ✓ Fits season (37 days to spare)
Start indoors: Mar 16 Transplant: May 25 🍅 Harvest: Aug 3 – Sep 21

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 Ellis County

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

Soil pH

Your soil pH (6.5โ€“7.2) is within Sunflower's preferred range (6.0โ€“7.5).

Soil Texture

The loam soil in Ellis County is excellent for Sunflower โ€” good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (3.4%). Annual compost additions will help Sunflower.

How to Plant Sunflower

1"
Planting Depth
18"
Between Plants
30"
Between Rows

Succession Planting Sunflower

2
successive plantings in your 174-day season

Sow every 8 weeks. Last sowing by Jul 07 to harvest before frost.

Plant Water Budget

Plant needs
0.5″/week
Rainfall provides
0.5″/week
You supply
0.0″/week
Watering frequency Only during dry spells
Season total 23 gal / 100 sq ft
Drought risk

Water stress score is 8/10 โ€” consider drought-tolerant varieties and mulching

Monthly Watering Guide for Sunflower

Sunflower 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 Sunflower Needs Rainfall You Supplement Action
Jan โ€” 0.5" 0" โ„๏ธ Dormant
Feb โ€” 0.6" 0" โ„๏ธ Dormant
Mar โ€” 1.5" 0" โ„๏ธ Dormant
Apr 2.2" 2.1" 0.1" ๐Ÿ’ง Light watering
May 2.2" 2.8" 0" โœ… Rainfall sufficient
Jun 2.2" 3.4" 0" โœ… Rainfall sufficient
Jul 2.2" 2.6" 0" โœ… Rainfall sufficient
Aug 2.2" 2.5" 0" โœ… Rainfall sufficient
Sep 2.2" 1.7" 0.5" ๐Ÿ’ง Light watering
Oct 2.2" 1.2" 1" ๐Ÿ’ง Light watering
Nov โ€” 0.8" 0" โ„๏ธ Dormant
Dec โ€” 0.6" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Aprโ€“Oct in Ellis County). Supplement amounts are based on average rainfall โ€” actual needs vary with temperature, soil, and mulching.

Sunflower 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" โ€” every day above 50ยฐF 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.

Sunflower needs ~1,488 GDD — county provides 3,045 GDD Excellent fit

Sunflower Planting Timeline โ€” Ellis County, KS

Sunflower Planting Calendar

Activity When Date Range
Start Indoors February 27 Feb 27 โ€“ Mar 13
Transplant Outdoors May 8 May 8 โ€“ May 22
Direct Sow May 1 May 1 โ€“ May 22
Harvest July 17 Jul 17 โ€“ Sep 4

Plant 1" deep ยท 18" apart ยท Rows 30" apart

Month-by-Month Timeline

MonthActivities
January โ€”
February Start Indoors
March Start Indoors
April โ€”
May Transplant Outdoors Direct Sow
June โ€”
July Harvest
August Harvest
September Harvest
October โ€”
November โ€”
December โ€”

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

0.5"/week ยท Only during dry spells

๐Ÿ“… Days to Maturity

70โ€“100 days

๐Ÿงช Soil pH

Needs 6โ€“7.5 ยท Your soil: ideal

๐Ÿ—บ๏ธ USDA Zone

Zone 6a

๐Ÿ“† Growing Season

174 days in Ellis County

Growing Tips for Sunflower in Ellis County

Direct sow Sunflower outdoors after April 24 in Ellis County when soil has warmed and frost danger has passed.

Common pests for Sunflower in this region include aphids and slugs. Use row covers early in the season and inspect plants weekly.

Ellis County receives only 20" of rain annually. Sunflower needs consistent moisture โ€” install drip irrigation or water deeply 2-3 times per week.

General growing tips

Direct sow after last frost. Stake tall varieties in windy areas. Harvest seed heads when the back turns brown and seeds are plump. Dry heads upside down.

Companion Planting

Good Companions

Avoid Planting Near

  • Potatoes

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Sunflower in Ellis County, KS?

Ellis County is in Zone 6a with an average last frost of April 24. Plan your Sunflower planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Ellis County, KS?

Ellis County, Kansas is in USDA Hardiness Zone 6a. The average last spring frost is April 24 and first fall frost is October 15.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Ellis County gardeners in Zone 6a organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

Free download. Plan your entire garden season in minutes.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Ellis County, KS. Local conditions may vary. Last updated: April 2026.