Growing fennel in zone 3a
(Zone 3a = an average winter low of -40°F to -35°F.)
In USDA zone 3a, the typical last spring frost is May 29 and the first fall frost is September 5. Here is when to plant fennel against those dates.
Start seeds indoorsApril 17 to May 1
Direct sow outdoorsMay 29
Expected harvestJuly 28 to August 27About 60 to 90 days from sowing.
These are zone 3a averages
Computed from 17 ZIP codes in zone 3a. Your town's frost dates vary; enter your ZIP for dates built on your nearest weather station.
Get my exact datesUSDA Plant Hardiness Zone Map, 2023. USDA Agricultural Research Service / Oregon State University PRISM Group. NOAA National Centers for Environmental Information, U.S. Climate Normals 1991-2020. Planting windows for fennel from Utah State University Extension. Zone dates are medians; local conditions vary.