USDA hardiness reference

Zone 8

Zone 8 represents an average annual extreme minimum temperature band of 10°F to 20°F. It describes winter cold, not vegetable planting dates.

Colder edge10°FZone 8a begins here
Subzone split15°FZone 8b begins here
Warmer edge20°FNext broad zone begins

What Zone 8 tells you

It provides a broad basis for evaluating whether a perennial plant is likely to survive a typical local winter minimum. The “a” and “b” subzones each cover five degrees.

What it does not tell you

How Gardiv uses it

Zone is optional context. The annual-vegetable planner uses your editable frost dates for schedule calculations and keeps the zone out of formulas where it does not belong.