Even though we live in the coldest area of Florida, as some newcomers have recently experienced firsthand, we can minimize freeze damage to our tender landscape plants through thoughtful placement.
Dr. Robert Black, former UF/IFAS Extension horticulture specialist, shares some sound advice on cold protection for the tender ornamentals that don’t particularly like our North Florida freezes in today’s article.
Obviously, the most important factors determining how badly a plant will be damaged by cold weather are how cold it gets and how long it stays cold. But we shouldn’t overlook the fact that certain characteristics of the planting site, and its location within the overall landscape, also affect the degree of injury a plant will receive during a freeze.
Surprising as it may sound, location has a lot to do with how well plants tolerate cold weather.
In deciding where to plant a tender landscape ornamental in North Florida, look for a spot with good air and water drainage. Air drainage may seem like a strange idea but it makes sense. We know that cold air is heavier than warmer air. You don’t want to plant a tender ornamental in a low area where the coldest air will collect and settle. The location should be open enough to permit air movement but it also should be protected from cold winds by other plants, hedges fences or similar barriers.
Good soil drainage is always important. If your plant is in a poorly drained spot, it can suffer root damage during wet weather. This will make the plant more vulnerable to cold injury when freezing temperatures strike.
We also know that shade can reduce cold damage. Plants in shady locations will go dormant earlier in the fall and remain dormant longer in the spring than plants in exposed locations. Plants in some degree of dormancy tolerate cold weather better than actively growing plants. So, from a cold protection standpoint, a location under pines or other trees that give light shade would be preferable for tender ornamentals that don’t need full sun.
Morning shade is particularly important. Plants that have been frozen will suffer less damage if they thaw out slowly. Plants exposed to morning sun will thaw more quickly than plants that have morning shade.
Larry Williams, UF/IFAS Extension Agent, Okaloosa County, February 12, 2015