Will Thuja Grow in Zone 10?

Zone 10

• USDA Zone 10 encompasses areas in which the average annual minimum temperatures in winter drop into the 30 to 40 degrees Fahrenheit range. Effectively, this is a region where winter frosts rarely occur. Regions in Zone 10 include coastal South Florida, the southernmost tip of Texas near Brownsville, much of inland Hawaii and coastal California, especially in the southern third of the state. These areas are described as subtropical in climate, with mild winters and warm to hot summers. In the Bay Area, summers remain rather cool but the winters are very mild.

Arborvitae in Zone 10

• Planting arborvitae in Zone 10 can be a short-term experiment. Planting an arborvitae in fall keeps the plant looking its best until the following year when either hot summer temperatures stress the plant, or the overly warm winter following doesn't create the required winter dormancy. Garden centers in Zone 10 most likely will not sell arborvitae that is not hardy for the area. Arborvitae have a much better ability to prosper on the West Coast, since the winters there are cooler and wetter compared to Zone 10 in southern Texas and Florida.

Zone 10 California

• The American arborvitae (Thuja occidentalis) and western redcedar (Thuja plicata) will grow in gardens in California, according to the "Sunset Western Garden Book," which divides the country into more climate zones and takes elevational differences into account. Grow both of these species, and their various cultivars, in Sunset Zones 16, 17 and 21 through 24. These coastal climate zones in California correspond to USDA Zone 10, with winter temperatures rarely dropping below 30 degrees.

Subtropical Region Alternative

• In milder, warmer winter parts of Zone 10, such as in South Florida and inland highlands of Hawaii, Thuja species don't survive more than one to two years. Instead, plant the closely related Oriental arborvitae (Platycladus orientalis). It demonstrates much better tolerance to warm winters in Zone 10 in Florida, especially in areas where winters do provide some temperatures ranging 30 to 35 degrees Fahrenheit, sometimes called zone 10a.