Best Management Practices
for Florida turfgrasses –
Fertility and Cultural
http://turf.ufl.edu
LAWN
Have you scalped the lawn?
 Used weed and feed more
than 2 times a year?
 Water more than 2 times a
week?
 Fertilize with quick release
fertilizer?

Then lets SHAPE UP!
Benefits of Turfgrass

Functional Benefits
 Stormwater
Runoff Reduction
 Soil Erosion
 Dust Stabilization
 Heat Dissipation

Aesthetic Benefits
 Safe Play Area
 Community Pride
 Increased Property
Values
 Compliments and
ties together the
rest of the
landscape
Components of
best management practices
Right plant, right place
 Fertility practices
 Irrigation practices
 Mowing practices
 Pesticide spraying

Which Grass Do
You Want to Use?
• Bahiagrass
• Bermudagrass
• Centipedegrass
•St. Augustinegrass
• Zoysiagrass
St. Augustinegrass
(Stenotaphrum secundatum)
Advantages





Good shade
tolerance
Good salt
tolerance
Tolerant to wide
range of soil pH
Establishes
quickly from sod
Dark green color
St. Augustinegrass
(Stenotaphrum secundatum)
Disadvantages
–Poor cold tolerance
–Poor drought
tolerance
–Poor wear tolerance
–Forms excessive
thatch
–Susceptible to chinch
bugs
St. Augustinegrass Cultivars
Floratam
Raleigh
Bitterblue
Classic
Amerishade
no longer chinch bug resistant
poor cold and shade tolerance
cold hardy
poor chinch bug resistance
good shade tolerance, blue green color
good cold tolerance
dwarf with good shade tolerance
St. Augustine dwarf cultivars
•Captiva New dwarf cultivar with great shade
tolerance and chinch bug resistance
•Seville Great shade tolerance prone to
thatch and webworms
•Delmar cold tolerant- good for sun too
Zoysiagrasses
(Zoysia spp.)
Advantages
 Tight low growing turf
 Good shade tolerance
 Resists weeds
 Good traffic tolerance
 Disney grass
Zoysiagrasses
(Zoysia spp.)

Disadvantages




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Slow growing
Thatch issues
Water needs
Fertilizer needs
Billbugs
Nematodes
Zoysiagrasses
cultivars
Empire
 El Toro
 Ultimate flora




Lush look of a Northern-type lawn grass for
warm-season climates.
Easily replaces St. Augustine grass as a
residential turfgrass option.
Establishes quicker than most other zoysia
grasses.
Bahiagrass
(Paspalum notatum)

Advantages





Good drought tolerance
Low fertility
requirements
Low maintenance
Tolerant of sandy,
infertile soils
Establishes from seed
Bahiagrass
(Paspalum notatum)

Disadvantages





Produces abundance of
seedheads
Open growth habit
encourages weed
competition
Susceptible to mole crickets
Coarse stems are difficult to
mow
Not wear tolerant
Centipede grass

Advantages





Slow growing
Good drought tolerance
Low fertility requirements
Low maintenance
Tolerant of sandy, infertile soils
Hammock is a good cultivar
Centipede grass

Disadvantages



Poor shade tolerance
Nematodes
Can be over managed
Fertilization
Goals of fertility programs
1. To produce healthy, stresstolerant turfgrass
2. To protect the environment
Turfgrass Fertility Considerations
Soil testing
 How to apply fertilizer to not pollute
 Fertilizer source (quick-release vs.
slow-release)
 Application amount
 Application timing
 Fall fertility
 Fertilizer storage

Know Your Soil



Soil testing should
provide the basis for
determining a fertility
program
This includes pH
testing as well as
extractable levels of
macro and
micronutrients
Do not soil test for N,
as it is very mobile
pH
If you soil pH is too low less than 6 you
will need to apply Lime
 Only apply lime with recommendations
from your soil test
 Use either calcitic limestone or dolomite to
lime
 Water in with ¼ inch of irrigation
 It will take 4-6 weeks for you to get the
pH were it needs to be

The Fertilizer Bag



Numbers refer to
percent nitrogen,
phosphorus, potassium
in the bag
Example: 15-0-15 has
15% N, (or 7.5 lbs. in a
50 lb. bag) 0% P, 15%
K as K2O5
Nutrient sources also
listed
Turfgrass Fertility Considerations
How to apply
 Fertilizer source (quickrelease vs. slow-release)
 Application amount
 Application timing
 Fall fertility

How To Properly
Apply Fertilizer

Be careful not to apply fertilizer particles
onto sidewalks, roadways, or other
impervious surfaces where they might
wind up in the storm drain
How To Properly
Apply Fertilizer

Use a deflector shield when fertilizing near
water bodies- this will allow for a 3’ ring –
without a shield, leave a 10’ ring
How To Properly
Apply Fertilizer

Irrigate fertilizer in with only enough
water to move granules off of leaves
(~1/4” water)
Elements Required
for Turfgrass Growth
Macronutrients: Micronutrients:
From
Nitrogen
Environment:
Carbon
Hydrogen
Oxygen
Iron
Phosphorus
Manganese
Potassium
Boron
Calcium
Copper
Magnesium
Molybdenum
Sulfur
Zinc
Nickel
Application Amount
Depends on percentage slow-release N
 No more than ½ lb. N 1000 ft2 if quickrelease
 Up to 1 lb. N 1000 ft2 if slow-release
 Better to apply smaller amounts more
frequently for optimal physiological
functioning of turf

T-Timing
1.
2.
3.
4.
The first fertilization is in the
Spring -early April
Then May with slow release
Fall fertilization is done in
September-October
Weed control is addressed in
late February early March
Current UF/IFAS Fertility
Recommendations
(lbs. N 1000 ft-2 yr-1)
St. Augustinegrass:
North FL:
2-4
Central FL:
2-5
South FL:
4-6
Current UF/IFAS Fertility
Recommendations
(lbs. N 1000 ft-2 yr-1)
Bahiagrass:
North FL:
Central FL:
South FL:
2-3
2-4
2-4
Current UF/IFAS Fertility
Recommendations
(lbs. N 1000 ft-2 yr-1)
Centipedegrass:
North FL:
Central FL:
South FL:
1-2
2-3
2-3

Current UF/IFAS Fertility
Recommendations
(lbs. N 1000 ft-2 yr-1)
Zoysia grass:
North FL:
2-4
Central FL:
3-6
South FL:
4-6
Current UF/IFAS Fertility Recommendations
(lbs. N 1000 ft-2 yr-1)



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To apply 1 pound of NITROGEN per 1000 square
feet
Take the percentage nitrogen from the fertilizer
label 10-2-10 and divide that into 100. The result
will equal the pounds of FERTILIZER to apply to
1000 square feet.
For a 15-0-15
15/100 = 6.5 pounds of fertilizer to 1000 square
How Much Phosphorus
Do We Need in Florida?
•
•
•
P fertilization should be based on
soil test results
If a soil test indicates P is
adequate in soil, use a fertilizer
with no more than 2% P
P may be required in greater
amounts during establishment of
lawns
Fertilizer Rule
in Florida on Phosphorus


This rule limits fertilizers that can be sold for use
on lawns to those that contain low or no
phosphorus (2nd number on the bag), and
limits the total annual amount of phosphorous
that can be applied to a home lawn.
You are allowed to apply 1 pound of nitrogen
per 1,000 square feet of lawn each time you
apply fertilizer if the nitrogen is in a slow-release
form, or 0.7 pounds of nitrogen if you are using a
quick-release source.
Potassium Provides Increased
Tolerance to Many Stresses
•
•
•
Helps turf maintain water balance
Functions in cellular activities such
as photosynthesis
Can enhance cold tolerance and
spring green-up
Other Considerations
for Fertility: Irrigation
Even if fertilizer is applied at proper
rates, too much water following
fertilizing can result in leaching or
runoff
 Irrigate fertilizer in with ¼” of
water
 Don’t fertilize during a heavy
rainfall

It’s raining out- should we leave the
sprinklers on?
An efficient watering
program must
include:
 How frequently to
water
 how much to water
 time of day to water
How Often to Water

The most efficient
way is to apply
water when turf
begins to show
signs of stress:
 bluish gray
color
 footprints
remain
 leaf blades
folded in half
How Much to Water
•An efficient watering only wets the turfgrass root
zone, does not saturate the soil, and does not allow
water to run off.
•Apply 1/2” to 3/4” when turf shows symptoms of
wilt and do not apply any more until water stress
symptoms are again noticeable.
Short, frequent
irrigations
Longer, less frequent
irrigations
Time of Day To Water
 Wet
grass = disease
opportunity
 Dew point should not be
extended – grass must dry
out
 Best time to water is just
before or at sunrise
Irrigation System Efficiency

One of the most
important things to
do during a
drought is to check
the efficiency of
your irrigation
system
We are under Watering
Restrictions
Water only one time per week.
 Even addresses Sunday
 Odd addresses Saturday
 No watering between 10 am and 4 pm
 Check with GRU or St. John’s River
Water Management district for more
information.

Mowing
• Don’t mow
grass when wet
•Keep mower
blades sharp!
Mowing
Mow at highest recommended height
for species
 Don’t remove more than 1/3 of the
leaf blade at any one time
 Leave clippings on the ground
 Increase mowing height under any
environmental stress (shade,
drought, etc.)

Influence of mowing height on
rooting depth
Mowing Under Drought Conditions


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Grass growth is reduced during drought
Therefore, mowing needs are reduced
You should mow less often, but at the
highest recommended height for your
grass. This will help to encourage a
deeper root system and place less stress
on the grass
Keep your mower blades at their sharpest
to further reduce stress on the grass
How Do I Manage
Turf in the Shade?




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Remove shade sources (trimming trees)
Reduce traffic in shaded areas
Increase mowing height if possible –
more shoot tissue for photosynthesis will
help turf perform better
Reduce irrigation in shaded areas
Reduce fertilization – trying to promote
shoot growth with high fertility will
further stress the grass
Shade Tolerant Turf
St. Augustinegrass = zoysiagrass
Centipedegrass
Bahiagrass
Bermudagrass
St. Augustinegrass Shade Tolerance
 Captiva,
Seville, Delmar,
 Bitterblue
 Palmetto
 Floratam
Weeds
Broadleaf
 Sedges
 Grass weeds

Weed Control Begins With Proper
Management

Proper Turfgrass Selection


Proper Cultural Practices


This results in thin, weak turf that is very susceptible to
weed invasion
Proper fertilization, watering, mowing, and control of
other pests are required to produce a dense turf that will
prevent weed infestation
Sanitation

Many times we introduce the weeds
Chemical Controls
Selective, Non-selective
 Contact, Systemic
 Pre-emergence



applied prior to weed seed germination
Read your herbicide label very carefully
Hawksbeard
Spreading Dayflower
Dollarweed
Crowfootgrass
crabgrass
Pendamethalin
Halts crabgrass preventer
Sandspur
Globe Sedge
Nutsedge
Basagran
Manage
Image
Hand weeding can work!
Diseases

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Gray leaf spot
azoxystrobin,
propiconazole,
thiophanate methyl,
trifloxystrobin.
Diseases

Brown Patch now Large patch

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Cool weather disease
mancozeb,
azoxystrobin
propiconazole
thiophanate methyl
Insects
Chinch bugs
Chinch bugs
 Suck the plant juices from grass (generally on nodes
of runners) resulting in yellowish to brownish patches
 Damage often first noticed in water stressed areas
along edges of lawns
Treat with triazicide or bifenthrin
Tropical Sod Web Worms



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Summer and fall
Notched feeding on
blades
Associated with
moths
Dipel or Sevin
Grubs

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Grass thins, yellows,
wilts, dies.
No roots
Many different beetle
culprits
Grub Ex
Inspecting for Grubs
Treat with labeled pesticide
Monitoring for Turf Pests
Weekly pest monitoring is recommended
Monitoring Chinch Bugs
1) Insert open ended metal can 2 inches into soil
in suspected areas
2) Fill can with water, chinch bugs will float
3) Wait 5 minutes
then count
4) Repeat in 3 - 4
locations
In general, healthy turf is
better able to withstand pest
pressure than stressed turf
Follow guidelines for growing healthy
turf printed in the Florida Lawn
Handbook