Fall Fertilizing

Fertilizing is an important aspect in keeping a healthy lawn.  The three main nutrients for turfgrass are nitrogen, phosphorous and potassium.  Nitrogen enables turfgrass to make chlorophyll which is used to perform photosynthesis.  Phosphorous is important for growth and potassium helps turfgrass become hardy against certain stresses such as drought and traffic stress.   Most of Florida’s soil has enough phosphorous to supply the nutritional needs of a lawn, but nitrogen and potassium need to be supplemented in the form of fertilizer. 

The amount and frequency of fertilizer applications vary with each species of grass.  Below is a chart showing the proper amount and frequency of fertilization for each species in a growing season. 

Nitrogen fertilizer recommendations for Florida turfgrass species

Species/location in Florida	Interim N recommendations (lbs 1000 ft-2 yr-1)*, **
Bahiagrass – North	2–3
Bahiagrass – Central	2–4
Bahiagrass – South	2–4
Bermudagrass – North	3–5
Bermudagrass – Central	4–6
Bermudagrass – South	5–7
Centipedegrass – North	1–2
Centipedegrass – Central	2–3
Centipedegrass – South	2–3
St. Augustinegrass – North	2–4
St. Augustinegrass – Central	2–5
St. Augustinegrass – South	4–6
Zoysiagrass – North	3–5
Zoysiagrass – Central	3–6
Zoysiagrass – South	4–6
*Homeowner preferences for lawn quality and maintenance level will vary; therefore, a range of fertility rates is recommended for each grass and location. Additionally, effects within a localized region (i.e., microenvironmental influences such as shade, drought, soil conditions, and irrigation) will necessitate that a range of fertility rates be used. **These recommendations assume that grass clippings are recycled.

Image retrieved from: http://edis.ifas.ufl.edu/ep435

Although fertilizer frequency differs with each species, the growing period is the same for all species growing in the same climate.  An actively growing lawn needs nutrients.  Your lawn should be fertilized as soon as spring green up occurs with subsequent applications throughout the growing season. 

For all of us living in Florida, the last fertilizing period is here.  We should give our grass one last application.  So dust off the spreader and pull out the fertilizer bag this weekend or next.  When you are done, pack it up for the winter and know your fertilizing job is done for the year.   

References:

Trenholm, L. E., Kruse, J. K., & Unruh, J. B. (2010). The Lawn Fertilizer Toolbox. Retrieved form University of Florida, Gainesville, IFAS Extension website: http://edis.ifas.ufl.edu/ep435

Unruh, J. B., Trenholm, L. E., & Cisar, J. L. (2011). Centipedegrass for Florida Lawns. Retrieved form University of Florida, Gainesville, IFAS Extension website: http://edis.ifas.ufl.edu/lh009

 

The Proper Amount of Water

The excessive amount of rain in Gainesville these past months has caused grief and heartache for three homeowners in my neighborhood.  The reservoir area behind their home is flooded and running into their yards leaving their soil constantly saturated.  The lawn of one homeowner, sadly, is dying.  I am not sure if the grass is dying from a fungus or from the roots not getting enough oxygen.  Watching these lawns struggle I ask the question, "what happens when a lawn gets too much water and how much water does it need?"  According to Trenholm, Unruh, and Cisar (2006), too much water can cause a poor root structure, a build up of thatch, and can cause the turf to become susceptible to fungus and insect infestation.  I am sure that I am among many friends when I say that I have had problems with bugs and fungus in my yard this season.  Although the excess water has been due to rain this season, during dry weeks when homeowners over irrigate their lawn are actually inviting fungus and insects to live in their lawn.  This brings me to the second half of my question, how much water does a lawn need?  The short answer is it depends.  It depends on the type of grass you have and how hot it is.  Some of the signs you can look for in your lawn to know when it needs water are when the leaf blade will fold in half, the grass will turn a green gray color, and the grass will not pop back up immediately after walking on it.  During our next dry spell instead of turning your sprinkler system back on to automatic timer, try watching your lawn to give you the signs that it needs water.  Give it a good soak only when your grass is ready for a drink and know that you are helping it resist those pesky insects and fungus. 

           
Watering Your Florida Lawn
 

The tire tracks from the lawnmower show how saturated this ground is.

This homeowner mowed his lawn over a week ago.  There has not been any new growth and many of the blades have turned brown. 

 

Reference:

Trenholm, L.,Unruh, J., & Cisar J. (2006). Watering Your Florida Lawn. Retrieved form University of Florida, Gainesville, IFAS Extension website: http://edis.ifas.ufl.edu/lh025

 

 

Why St. Augustine!?!

Two years ago I moved to Gainesville. I had made it a priority on my house shopping list to find a house without St. Augustine grass. I almost cried when I saw that almost every yard in Gainesville had St. Augustine grass.  Why don't I like St. Augustine grass?  Let me tell you.

Prior to moving to Gainesville, I lived in Pensacola Florida.  The climate is similar to Gainesville with the exception of the winters being a little colder, but only by a few degrees.  The grass of choice for Pensacola yards is centipede grass.  My front yard had centipede, but my back yard had St. Augustine.  Not knowing much about grass, I did not do much other than water and cut the grass.  Shortly after moving in, I noticed a large area of the St. Augustine grass dying.  Not knowing what to do, I called a lawn service company and $200 later the cinch bugs were killed.  I vowed never to spend that kind of money on my lawn again, and decided to research how to maintain St. Augustine grass.  My research lead me to find that most herbicide and pesticide products available on the market can not be used on St. Augustine grass.  The product will inevitably kill the weed or pest, but it will also kill the grass.  In the four years I lived in Pensacola, I struggled to keep the St. Augustine grass alive.  Between the cinch bugs, sod web worms, weeds, and fungus, there was very little St. Augustine grass left.

My front yard; however, was different.  The centipede grass required very little care.   Not once did it get infested with bugs, or fungus, and I was able to spot spray any emerging weeds with Weed-B-Gone without damaging the grass.  It always looked green and healthy.

Happy to be rid of my Pensacola back yard, I was ready to find a centipede sodded yard in Gainesville.  Needless to say I did not find such a yard. Less then a month after moving into Gainesville my lawn started to look bad.  It had a fungus.  Knowing I could not let both my front and back yard turn into weeds, I broke down and hired a lawn service company to maintain pest and weed control and to fertilize the lawn.  I just moved again into another house in Gainesville this summer.  The St. Augustine was well kept by the previous owner.  I did not start up lawn service immediately, and shortly after moving in the grass began to look bad.  It had sod web worms.  Again, I had to hire a lawn service.  The lawn service man forgot to spray a section of the grass.  A week later I realized that section was getting worse instead of better.  By the time the service man could come back again to spray, the majority of the grass had died.  It has been just a little over a week since the grass was sprayed and some of it is coming back, but now the area will be susceptible to weeds.  St. Augustine grass is so frustrating!

All the problems I have had with St. Augustine grass has led me to ask why is it preferred over centipede grass in Gainesville.  I called three local nurseries and asked if they carried both St. Augustine and centipede grasses.  They all did, so both species are available to the public .  I compared the price of a pallet of grass to see if that was a factor and found one nursery's price for centipede was cheaper than their price for St. Augustine; one nursery priced both grasses the same; and one nursery's price was higher for centipede than their price for St. Augustine.  Not only were these nurseries inconsistent with which product they priced higher, they ranged in price from $125 to $250 a pallet.  Price is clearly not a factor.

This leads me shade tolerance.  If comparing St. Augustine with centipede for shade tolerance, St. Augustine will win.  There are a lot of trees in Gainesville yards which require the most shade tolerant grass, but not all yards are created equal.  Next time you drive through a Gainesville neighborhood, look at how many front yards are treeless or have just one or two small trees that do not give off much shade.  Look at their grass.  Is it St. Augustine or centipede?  More than likely it is St. Augustine.  My goal is to prescribe the right plant for the right area for my future clients.  Unless my opinion about St. Augustine grass changes, I will be prescribing centipede grass to all homeowners with a sunny lot. 
              
http://edis.ifas.ufl.edu/ep072