Lawn Fertilization Schedule
For Southern Grasses including St. Augustine, Bermuda, and Zoysia.
The following schedule is courtesy of Randy Lemmon, host of GardenLine, a radio program on AM Newsradio 740 KTRH. Randy has been hosting GardenLine in one capacity or another since December of 1995, for AM stations – KTRH, KPRC, and KBME. When Randy took over GardenLine, he replaced long-time Houston radio veteran and GardenLine originator, Bill Zak.
For a printable version of this chart for your refrigerator, download Randy’s one-page fertilization schedule.
Fertilize (4 Times, Yearly)
Late February to early March
Apply a simple 15-5-10 for an early green up. Most companies that make slow-release fertilizers also make non-slow-release 15-5-10 that provides for quick two-week green up before we get to the heart of the fertilizer schedule. Some people will be tempted to use a weed-and-feed at this time, but if you’ve been following the Garden Line herbicide schedule, there should never be a need. However, spot weed-and-feed contain Atrizine which burns roots of young trees and shrubs.
Late March – early April
Apply slow-release 3-1-2 ratio fertilizers.
- 19-4-10 Nitro Phos Super Turf
- 18-4-6 Fertilome Southwest Greenmaker
- 18-0-6 Fertilome’s Zero Phosphate Formula
- 15-5-10 Southwest Fertilizer Premium Gold
- 19-5-9 Easy Gro Premium
- 21-5-10 Mr C’s (Cornelius brand)
Late June – early July
Apply slow-release 3-1-2 ratio fertilizers. (Recommended formulations: 19-5-9, 19-4-10, 18-4-6, 15-5-10)
October – November
Apply winterizer formulas for winter hardiness. Ratios vary, but make sure they are “winter” or “fall” formulas designed for Southern Grasses. (Examples: 16-6-12, 8-12-16, 10-5-14) These will make lawns winter-hardy.
June – September
If turfgrass looks yellow (chlorosis) or necrotic, use an application of either granular or liquid iron. Once a year should be enough.
Fungicide (Twice Yearly)
July – September
Gray Leaf Spot – Treat with Daconil, Consan, or Banner. Gray Leaf Spot is a blotchy spot on the grass blade leafs. (Mostly on St Augustine lawns) Use fungicide ingredients like Daconil, Consan, or Banner.
September – October
To control the dreaded Brownpatch fungal disease (symmetrical brown circles in the grass) you must prevent it from coming up with a systemic lawn fungicide with Bayleton, Tarrachlor, Banner, or Benomyl.
Herbicide (3-Times, Yearly)
Be careful using non-selective herbicides, you just may kill everything. Pre-Emergent controls to prevent weeds.
Late October – early November
Use two different pre-emergent herbicides, to prevent the weeds that we experience in February and March. First is a pre-emergent with Protrait or Gallery for broadleaf weeds like clover. Second, use a pre-emergent with Amaze, Betasan, Balan, or Treflan. There is also Barricade, Dimension, or Pendimethlin as a 2-in-1 control.
February – March
Use the pre-emergent controls for grassy weeds again, to prevent such weeds as Crabgrass, Goosegrass, and Dallisgrass from popping up late in the spring and summer. Again, use the grassy pre-emergent like Amaze, Betasan, Balan, or Treflan. There is also Barricade, Dimension, or Pendimethlin as a 2-in-1 control.
May – Early June
One more application of a grassy pre-emergent like Amaze, Betasan, Balan, or Treflan will keep fall weeds from invading from August on. There is also Barricade, Dimension-based or Pendimethlin as a 2-in-1 control.
It is our belief on Garden Line, as a way to be kind to the environment, that you do not put down insecticides unless you know you have a problem.
However, be prepared during the hot summer months (July through September), to attack chinch bug damage. This will show up as irregular shaped spots in the lawn along the concrete.
Any liquid insecticide, like Permethrin or Cypermethrin, will treat the spot well. Then apply a granular insecticide like Deltamethrin or granular Permethrin in a broadcast applicator throughout the rest of the yard.