Give your Florida landscape a break this winter

Central Florida can be a challenging location when it comes to maintaining a landscapes during the winter months, because of our frequent temperature fluctuations. The Tampa Bay area is no different from most of central Florida.

Let’s begin with three basic concepts: identify the landscape plants you have; be knowledgeable about the plants’ maintenance requirements; and consider natural seasonal changes in sunlight and temperature.

In general, newcomers to Florida, as well as seasonal snowbirds, expect all plants in Florida to be green year-round. That is not natural, even in the Tampa Bay area. As a result, we tend to love our landscapes to death.

When the fall and winter seasons arrive, we have cooler temperatures and shorter daylight hours. At the University of Florida, Institute of Food and Agricultural Sciences Extension in Hillsborough County, I frequently hear folks say, “It’s cool outside, fall is finally here.”

Plants know the season is changing by the length of daylight hours, known as the photoperiod. When daily light gets shorter, plants respond. Plants are either long-day plants or short-day plants. When deciduous trees change color or drop leaves, they’re responding to shorter days. The slowing of turfgrass growth is a response to shorter days.

Most of our landscape plants respond to shorter days by slowing their growth. There is less sunlight, and as a result, less photosynthesis. That translates to plants such as turfgrass needing less water, fertilizer and pesticides because growth has slowed.

Turfgrass photosynthesis slows so much that some of the root system reduces, and it cannot use water or nutrients. It wants to go into dormancy, but our usual above-freezing temperatures of the Tampa Bay area keep it from going into complete dormancy. During this semi-dormant state, we need to mow less frequently. And because the grass is not growing, it needs minimal water and no fertilizer.

Here are some other winter landscape maintenance tips:

• Make the last fertilizer application during November. Make the first spring fertilizer application in late March or early April, once turfgrass has begun to grow on its own. When grass starts to look green, that’s its way of telling you that the daylight hours are getting long enough for photosynthesis to increase and promote growth that requires nutrition. Fertilization during the winter promotes tender growth that is more susceptible to cold damage. Always check and follow your county or municipal landscape and fertilizer ordinances. These rules apply to all residents.
• Irrigate when plants need supplemental water and not on a preset schedule. Turfgrass leaf blades fold in half and take on a blue-gray tint when the soil does not have enough moisture. Footprints may also remain visible on the grass for a while. In general, supplemental irrigation may be needed about every 10-14 days, rather than twice per week.
• If you suspect an insect or disease problem, always identify the pest or disease prior to applying pesticides. Cultural practices, such as over-irrigation or over-fertilization, often are the cause of problems and can be corrected easier and less expensively than applying pesticides. Read the label for application instructions and to make sure the product is safe for your turfgrass or plant cultivar.
• To control winter weeds, make pre-emergent herbicide applications when nighttime temperatures drop to 55-60°F for several consecutive days (October to November) and repeat in early winter (December to January).
• Refresh mulch in ornamental beds to a settled depth of 3 inches. Beds occasionally need decomposed mulch removed to prevent excessive mounding of beds.
• Prune only dead, dying, diseased, or deranged branches from shrubs and trees. Pruning encourages new growth that may be damaged by cold weather. Perform structural pruning in February or early March. Some shrubs set buds in the summer or fall, and any pruning after buds have set or during the winter will reduce blooms the following year.

Overall, you can cut back on maintenance dramatically during the winter season. Take a break, save some water and money, and enjoy the season.

Susan Haddock is the commercial horticulture and integrated pest management agent for UF/IFAS Extension Hillsborough County. Contact her at szcrmchz@ufl.edu, or (813)744-5519 ext. 54103.

Contact your local Extension Office for more information:

• Hernando County: hernandomg@ifas.ufl.edu
• Hillsborough County: hillsborough@ifas.ufl.edu
• Pasco County: Greich@pascocountyfl.net
• Pinellas County: gardenhelp@pinellascounty.org