Florida winter landscape management and pest prevention

Massey Services' Joe Welch gives a perspective on providing winter service in the southeast.

January 24, 2014
Joe Welch
Web Extra

Florida lawn and landscape care is vastly different than in just about any other state in the country, particularly in the winter. Here in the Sunshine State it’s a year-round business. There’s no break to refurbish equipment like there typically is during the winter months in northern states and maintenance must be factored in between service appointments. There’s no need to find alternative services to provide when not tending to the lawn and landscape, such as snow removal or Christmas lighting. Florida’s winter temperatures are more typical of fall temperatures in other parts of the country. What we would regard as winter is typically about a 30-day period somewhere between the middle of December to the middle of January when an occasional cold front may bring us a frost or potentially freezing temperatures. There have been some years where Florida’s winter temperatures plunge into the 40’s in the daytime for a week or two, but that is rare.Other than the month or so of winter weather, what we really deal with is an extended fall, followed by an early spring. This is particularly true in Central Florida. Southern Florida, Miami and the Keys, experience even less of a winter where a frost or freeze would be extremely rare.

In summer or winter, curb appeal is the first thing most people notice about a Florida home. While grasses in other parts of the country may go dormant in the winter, Florida’s warm season grasses, primarily St. Augustine, do not go into a true dormant state. Leaf production is reduced to a point where mowing is only required every two weeks, unlike in the summertime when grass needs to be mowed every five to seven days. The stress of summer’s heat is also gone. With lower humidity and temperatures typically in the 60s or 70s, the labor involved in lawn and landscape services becomes pleasant, as compared to June, July and August, where temperatures hover in the high 90s and the humidity makes landscape maintenance seem like punishment.

While it’s definitely less intensive and much more pleasant to manage lawns and landscaping during the Florida winter, landscapes still require turf fertility and pest management throughout the cool season. In fact fall and winter fertilization has become even more important in some parts of Florida where some misguided local municipalities have imposed harsh and agronomically unsound restrictions on summer fertilization. These restrictions cause lawns and shrubs to become nutrient deficient and less healthy, which in turn make them more susceptible to catastrophic damage should pests, or a frost or unseasonably cold weather occur.

From September through November, with the change in the growth pattern of the turf from being upright to prostrate, fertilizer applications are utilized to help build up food reserves in the plants in preparation for the winter. Nitrogen fertilizer is increased at this time and can produce a darker color turf than what we usually achieve with our relatively light green St. Augustine turf. This time of the year is when lawns typically have the best appearance. Potassium fertilizer rates are increased as well to improve turf hardiness in preparation for potential, but rare, freezing temperatures.

December and January are typically the months Florida landscape managers begin preparations for spring. Nitrogen sources with a microbial release mechanism such as methylene urea can be utilized at rates up to one pound of N to prevent unwanted growth response and will make the applied nitrogen available to the turf when warmer temperatures arrive. Florida’s “spring” typically begins in February and lasts through May, though cold snaps can occur in February and March. During this time nitrogen application rates are typically one pound per 1000 sq. ft. utilizing a 50 percent slow release granular blend. 

Fertilization applications to landscape ornamentals in the winter should be very light or completely withheld until spring as a precaution for potential freezing temperatures, and to eliminate the chance of damaging the flower buds that were set in the fall.

The cooler months are also a good time to manage large plantings in the landscape. This is the time for installation or transplanting trees and woody ornamental shrubs because the months of cooler weather are less stressful on the trees and shrubs and root growth is enhanced. Applications of nitrogen sources from organic biosolids are beneficial to aid in root production. Getting shrubs and trees established early in the year is essential for survival before the typically dry season in April and May. 

There are still many challenges that landscapes face during the winter months. Insect pressure from chinch bugs, sod webworms and other lawn caterpillars is practically nonexistent during a cold winter, but can remain a problem if the winter weather is warmer than usual. The primary turf problems dealt with in the winter are Rhizoctonia soloni (Brown Patch), as well as perennial and winter annual broadleaf weeds. Lawns with a history of Brown Patch fungus should be given an application of preventive fungicide in September or October, which may be repeated according to label directions during conditions conducive for development. Winter annual weed issues are prevented with pre-emergence herbicides applied in late summer and repeated in December or January. Florida’s primary influx of cool season annual weeds occurs in March and April. The pre-emergence applications do well to prevent this problem; however, post-emergence herbicide applications will be required for spot treatments.

The cooler temperature range is perfect for the development and growth of fungal pests and is often exacerbated by excessive irrigation as some continue with summer irrigation schedules. Because the Florida winter is mild, insects don’t die off to re-emerge in the spring.  Insect damage to landscape shrubbery continues throughout the winter, particularly scales and spider mites. Aphids and thrips also contribute to cause damage. While the number of these insect pests may be somewhat reduced due to their slower reproduction during the cooler weather, they are a constant threat. Even after some of our coldest periods on record, Floridians often find cold damaged shrubbery with seemingly healthy insects or spider mites feeding on whatever foliage are available after a frost.

Disease issues on landscape shrubbery are less of a problem during the winter, but do exist. The primary culprit is various species of Cercospora leaf spotting fungi. Protecting susceptible plant foliage through preventive fungicide application is the key. With the reduction of new growth during the winter, visual recovery that is apparent will not occur until March or April when the spring growth flush occurs.

Florida lawn and landscape care is a constant challenge. The state’s soils are not rich with organic matter and lack water-holding capacity. The insect pressure in the summer months can be overwhelming, but lessen in winter. Our lawns may not have that barefoot softness like ones in the northern climates, but with proper care they can look great. The summer stress may weaken lawns and the daily afternoon thunderstorms in the summer may stimulate disease issues and hamper our ability to get our work done but when the cool season comes, it’s great to practice our craft of pest prevention and landscape maintenance in a state that others only enjoy on a temporary basis as visitors or snow birds. We work hard to create and care for beautiful landscapes that increase property values and enhance our environment. 

By Landscape Technical and Training Director, Joe Welch, Massey Services, Inc.