Patricia M. Arledge, Sharpe, Kenneth W. | 11/5/2014 9:07:03 PM
News Article for April 14, 2014:
We are now in the window of opportunity for both fertilizing your lawn and controlling weeds in your lawn grasses.
I just completed the second cutting of my grass and that means that it is growing good enough to take up the fertilizer now. Now the grass roots are establishing and the cool nights are diminishing, but not gone.
If you like the weed and feed products now is ideal. Just be sure you read the label correctly to make sure the product is labeled for your grass type and check out the application rate. Some of these products have very specific requirements of when to apply for maximum weed control. Calibrate and apply the correct amount per 1000 ft2 accurately.
A general fertilizer application rate for southern warm season grasses will be to use one-half pound to one pound of nitrogen per 1000 ft2. I like to use the one-half pound rate for maintenance and one pound if I need a lot of extra repair and growth. To accomplish the half pound rate, apply 6 pounds of 8-8-8 fertilizer per 1000 ft2 of lawn area or 4 pounds of 13-13-13 fertilizer. If you want to really cut grass then apply the one pound of nitrogen rate which will be 12 pounds of 8-8-8 or 8 pounds of 13-13-13.
Apply your fertilizers to a dry lawn and then water it in immediately after application. If you put fertilizer on damp grass, the fertilizer granules will stick to the leaf surface and burn the grass blades. By watering immediately after the fertilizer application you wash any fertilizer that lodges on a leaf on down to the ground and also prevent burns.
I have seen a lot of winter kill in area lawns. Not the whole lawn but obvious voids in which fertilizer will help to grow grass back in those spots.
After cutting my grass this last time I could clearly see all of the weeds that have invaded. Unfortunately my situation is the rule and not the exception; I see the same thing everywhere. You have about 5 weeks to remedy these problems before the heat of summer makes it too hot to apply herbicides. Not too hot for you, too hot for the grass to recover from the injury. Our lawn grasses cannot tolerate the herbicides once the temperatures approach 90˚ F.
I like a combination of a 2,4-D blend such as Ortho Weed B Gon, Trimec, Bayer Advanced Southern Weed Killer, Greenlight Wipe Out or Fertilome Weed Free Zone plus Atrazine. Mix the 2,4-D and atrazine together in the same tank and spray. This combination is very good on broadleaf weeds in warm season grasses such as centipede, carpet and St. Augustine grass.
These chemicals will be mixed with water and will be sprayed, so it is very important that you calibrate your sprayer accurately to get the correct rate per 1000 ft2 of lawn area. First, measure off 1000 ft2 in your lawn or on a driveway; then fill the sprayer with fresh water and see how much water it takes to spray 1000 ft2. Now you can add the amount of each chemical required per 1000 ft2 to the amount of water it takes. In my lawn with a 4 gallon backpack sprayer with a 4 nozzle boom walking at my pace it takes 96 ounces to cover 1000 ft2.
Pay attention to chemical drift and do not spray if the wind is above a light breeze. 2,4- D is notorious for drifting and it will harm your shrubs, garden vegetables and horticultural plants if it gets on them.
Atrazine will benefit from a rain or watering a few days after it is applied so it can be taken up by the roots, while 2,4-D is more of a contact kill.