PlantAlong

When to plant garlic in zone 7a

Plant for fall between Nov 1 and Nov 8. That is 1-2 weeks after zone 7a's median first frost, Oct 251. Across most of zone 7a that date falls between Oct 23 and Nov 16.

Why a range: zone 7a is defined by winter lows, not frost dates. Its ZIP codes have median first frosts from Oct 16 to Nov 22, so a single zone date can be weeks off for you. The rule comes from University of Wisconsin–Madison Division of Extension, Wisconsin Horticulture, written for WI and applied here to zone 7a's frost dates.

Last reviewed
Stations
865
ZIP codes
3,807
Photo: Chris F / Pexels
These dates use the typical last frost for the whole zone. Your ZIP code gives a closer answer.
  1. Plant for fallWisconsin
  • Start indoors
  • Plant outdoors
  • Range across the zone
  • Frost-free season (median)
  • Spring frost risk (90% to 10%)
  • Fall frost risk (10% to 90%)
Figure 1. Garlic in zone 7a. Dark bars: at the zone's median frost dates. Pale bars: across most of the zone's ZIP codes. Hatched blue: where the zone's last and first frosts fall.
Fall planting
Nov 11-2 weeks after first frost

Five digits. The calendar is computed on your device.

What each source says, applied to zone 7a

The same frost dates give different answers depending on whose rule you follow. These are all the published rules we hold for garlic, worked out at zone 7a's median frost dates.

Table 1. Garlic rules from every source, at zone 7a's median last frost (Apr 16) and first frost (Oct 25).
SourceWhatRuleZone 7a median
Minnesota3Plant for fall1-2 weeks after first frostNov 1 – Nov 8
Wisconsin1Used abovePlant for fall1-2 weeks after first frostNov 1 – Nov 8
Texas A&M (E-502)4Plant for fall4-6 weeks before first frostSep 13 – Sep 27

Frost across zone 7a

  1. Last spring frostmedian Apr 16
  2. First fall frostmedian Oct 25
  • Frost-free season (median)
Figure 2. Frost dates across zone 7a, from 865 NOAA stations matched to 3,807 ZIP codes.

Sources

  1. University of Wisconsin–Madison Division of Extension, Wisconsin Horticulture, Garlic, Allium sativum, Rev: 10/2023. Retrieved 2026-11-02.
  2. NOAA National Centers for Environmental Information, U.S. Climate Normals 2020: U.S. Annual/Seasonal Climate Normals (1991-2020), 2021. Retrieved 2026-11-02.
  3. University of Minnesota Extension, Fruit and Vegetable News blog, Tips for garlic planting season, Page shows October 15, 2026; URL path says 2021/10 (unresolved). Retrieved 2026-11-02.
  4. Texas AgriLife Extension Service, The Texas A&M System, Texas Home Vegetable Gardening Guide (E-502), 2/09. Retrieved 2026-11-02.