Are you ready to get tropical? Many residents of East Tennessee can do just that with their garden or outdoor landscape. The latest plant hardiness map released by the USDA in 2012 places Kingsport, Johnson City, and the I-81 corner between the Tri-Cities and Knoxville, in Zone 7A.
Why does that matter? Zone 7 is considered the outside limit for semi-tropical perennials to survive. That does not mean you need to start adding a plethora of tropical plants to your garden—especially plants rated in Zones 8 through 10. The re-zoning, however, gives you the option to add more tropicals, specifically for container gardens.
Consider working with microclimates. They give gardeners additional options and a greater chance of success when experimenting with tropicals for the first time. A microclimate can be created by simply planting near a south-facing brick wall, which absorbs heat during the day then radiates it at night, creating a warmer air effect near the wall itself. Planting near fences, large rocks or boulders will have a similar effect.
Urban areas are more likely to harbor sustainable tropical gardens. This is because the greater quantity of buildings and paved surfaces typically means less extreme low temperatures as compared to rural areas.
Wind protection is critical. Understand the way your prevailing winds flow and how they wrap around the home to help you decide which plants to choose and where to plant them.
A warmer microclimate will stay warmer year-round. That requires more maintenance—specifically, frequent watering—and it increases the chance that plants in a warmer microclimate might scorch due to the additional heat.
You can also create a cooler microclimate by planting in a valley or dipped area, or on the top of a hill.
If you have a question about growing tropical plants, call Promier Landscapes at (423) 246-7977 and a member of our staff will be happy to provide assistance.
Promier Landscapes offers design, construction, and maintenance services for outdoor landscapes for customers in East Tennessee between Kingsport and Knoxville.