When to Plant Fennel in Iowa
Iowa spans USDA hardiness 4b to 6a (zones 4b to 6a on this page). Plant fennel by your local frost date, not the calendar — pick your zone below for exact start-indoors, transplant, and harvest dates.
Jump to: Zone 4b · Zone 5a · Zone 5b · Zone 6a
Fennel planting calendar for Iowa, Zone 4b
Average last spring frost
May 10
Average first fall frost
September 25
Direct sow
Apr 26
Projected first harvest
Jul 25
Fennel is ready to harvest in about 90 days. Full zone 4 guide (both 4a and 4b) →
Fennel planting calendar for Iowa, Zone 5a
Average last spring frost
May 5
Average first fall frost
October 1
Direct sow
Apr 21
Projected first harvest
Jul 20
Fennel is ready to harvest in about 90 days. Full zone 5 guide (both 5a and 5b) →
Fennel planting calendar for Iowa, Zone 5b
Average last spring frost
April 30
Average first fall frost
October 5
Direct sow
Apr 16
Projected first harvest
Jul 15
Fennel is ready to harvest in about 90 days. Full zone 5 guide (both 5a and 5b) →
Fennel planting calendar for Iowa, Zone 6a
Average last spring frost
April 25
Average first fall frost
October 10
Direct sow
Apr 11
Projected first harvest
Jul 10
Fennel is ready to harvest in about 90 days. Full zone 6 guide (both 6a and 6b) →
Not sure which half-zone you're in? Set your ZIP in HomeSown for dates tuned to your exact location.
Varieties to grow
1 variety of fennel in the HomeSown library. Tap any for its full grow guide.
Common problems with fennel
What to watch for, with identification and treatment for each
🌱 Grow fennel with a calendar built for your exact yard
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