When to plant garlic in zone 7b

Plant for fall between Nov 8 and Nov 15. That is 1-2 weeks after zone 7b's median first frost, Nov 11. Across most of zone 7b that date falls between Oct 31 and Nov 28.

Why a range: zone 7b is defined by winter lows, not frost dates. Its ZIP codes have median first frosts from Oct 24 to Nov 142, 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 7b's frost dates.

Last reviewed
Stations
639
ZIP codes
2,958
These dates use the typical last frost for the whole zone. Your ZIP code gives a closer answer.

Garlic planting windows in zone 7b, computed from the zone's frost spread.

  1. Plant for fallWisconsinPlant for fall across most of the zone: Oct 31 to Nov 28Plant for fall at the zone median: Nov 8 to Nov 15 (Wisconsin)
  • 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 7b. 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 81-2 weeks after first frost

Five digits. The calendar is computed on your device.

What each source says, applied to zone 7b

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 7b's median frost dates.

Table 1. Garlic rules from every source, at zone 7b's median last frost (Apr 5) and first frost (Nov 1).
SourceWhatRuleZone 7b median
Minnesota3Plant for fall1-2 weeks after first frostNov 8 – Nov 15
Wisconsin1Used abovePlant for fall1-2 weeks after first frostNov 8 – Nov 15
Texas A&M (E-502)4Plant for fall4-6 weeks before first frostSep 20 – Oct 4

Frost across zone 7b

Zone 7b: median last frost Apr 5, most ZIPs between Mar 30 and Apr 17; median first frost Nov 1, most between Oct 24 and Nov 14.

  1. Last spring frostmedian Apr 5Full range across the zone: Mar 21 to Jun 3Most of the zone (10th to 90th percentile): Mar 30 to Apr 17Zone median: Apr 5
  2. First fall frostmedian Nov 1Full range across the zone: Sep 14 to Nov 26Most of the zone (10th to 90th percentile): Oct 24 to Nov 14Zone median: Nov 1
  • Frost-free season (median)
Figure 2. Frost dates across zone 7b, from 639 NOAA stations matched to 2,958 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.