Planting Zone 13b: Plants That Grow in USDA Hardiness Zone 13b

What Temperatures Define Hardiness Zone 13b?

Hardiness zone 13b is defined by an average annual extreme minimum temperature of 65 °F to 70 °F (18.3 °C to 21.1 °C). This is the warmer half of zone 13, which spans 60 °F to 70 °F in total.

The value is a 30-year average of each winter's single coldest night, taken from 1991–2020 weather records for the 2023 USDA map. Individual winters regularly run a few degrees colder, so plants rated exactly to zone 13bbenefit from mulch and a sheltered spot. Gardeners who don't know their zone yet can look up their USDA hardiness zone by ZIP code before comparing plants.

Which States Are in Hardiness Zone 13b?

Zone 13b doesn't occur in the contiguous United States. On the 2023 USDA map it is found in Hawaii and Puerto Rico, which the USDA ZIP code table doesn't cover.

What Plants Grow in Zone 13b?

60 plants in PlantoScan's catalogue are hardy in zone 13b, meaning zone 13b falls inside their hardiness range. They include 2 trees, 13 shrubs, 7 perennials, herbs & flowers, 28 vines & climbers.

How Do You Garden Successfully in Zone 13b?

Successful zone 13b gardens rely on perennials, shrubs and trees rated to zone 13 or colder. Plants rated right at zone 13b survive typical winters but benefit from mulch, windbreaks and a spot near a warm wall.

A hardiness zone describes winter cold only. Planting dates follow your local last spring frost and first fall frost, which differ by weeks within zone 13b — a last frost date calculator by ZIP code gives the dates for your garden. Summer heat, rainfall and soil drainage decide whether a hardy plant thrives. Microclimates matter as well: raised beds, slopes and paved areas warm up faster, while low ground collects cold air on still nights.