Example: Plano, TX (75024). Search above for your own place.
In zone 8b, the coldest night of an average winter bottoms out at 15 to 20°F (−9.4 to −6.7°C). A perennial, shrub or tree labeled hardy to zone 8 or a colder zone should survive the winter here.
| Zone | 8b (the warmer half of zone 8) |
|---|---|
| Average extreme low | 15 to 20°F (−9.4 to −6.7°C) |
| This ZIP's average coldest night | 16.7°F (USDA) |
| Plant tags to look for | a zone range that includes 8, such as "zones 5–8" or "zones 6–10" |
| Pushing your luck | plants rated only for zone 9 or warmer |
Average last spring frost: Mar 7; first fall frost: Nov 21. Planting times come from these, not from the zone. See the frost date lookup for the full range.
The zone tells you what survives winter, not when to plant. The zone is based on the average coldest night, not the coldest ever, so a hard winter can go below this range. Low spots, hilltops and city centers can also run colder or warmer.