When to Plant Corn (Sweet) in Zone 9b

Zea mays

Last updated: May 15, 2026 ยท Sources: USDA, NOAA, Cooperative Extension
Action Plan

Plant Corn (Sweet) in Zone 9b

  • Direct sow: Mar 14
  • First harvest: May 21 (60โ€“100 days)
โš ๏ธ Zone 9b last frost: Feb 21. Don't plant frost-sensitive crops before this date.
Last frost
Feb 21
First frost
Dec 2
Growing season
284 days
Zone 9b is the warmer half of Zone 9

Zone 9b has a last frost around Feb 21 and first frost around Dec 2, giving you approximately 284 growing days. This is about 2 weeks longer than Zone 9a. For more details see the Zone 9 complete guide.

๐Ÿ“š Data Sources
Frost dates: NOAA Climate Normals 1991โ€“2020, National Centers for Environmental Information.
Hardiness zones: USDA Plant Hardiness Zone Map, Agricultural Research Service.
Growing requirements: Cooperative Extension Services โ€” NC State, Penn State, University of Florida IFAS.
Companion planting: Cornell University Cooperative Extension.
Data compiled from public agricultural sources. Always verify with your local extension office for micro-climate adjustments.