UACES Facebook St. Augustine

St. Augustine

(June 2012)

QuestionWe used a pre-emergent herbicide on our lawn this year and it did not stop the progress of the weed called crabgrass. Is there something I can do to rid my yard of this grass?

AnswerThe standard herbicide for crabgrass control for years was MSMA and it is no longer on the market. We now have products that contain quinclorac for control. However most homeowner products are combined with another herbicide –many have 2,4-D (a broadleaf weed killer) which could burn warm season grasses when applied during the hot summer months –trade names include Weed-B-Gone Max, Weed Stop plus Crabgrass Killer and All in One Lawn Weed and Crabgrass Killer. Some products are combined with sulfentrazone—a sedge killer; trade names include Image Kills Crabgrass or Sedge and Grass Killer. Make sure if you are applying herbicides that you read the label beforehand. Follow recommended rates and read if there are any temperature restrictions and that it is safe for the type of lawn you are growing. Many herbicides are not recommended for use on St. Augustine or Centipede lawns. Also, make sure that the lawn has ample moisture before applying chemicals or fertilizers or you could damage the lawn. Don’t spray on a windy day and don’t treat the entire yard if you just have a patch here and there—spot spraying would be much safer.


(May 2012)

QuestionWe are having a problem with dead patches in our lawn. We have had a lawn service for 3 years who fertilize every 4 months and apply weed pre-emergence once a year. I understand dead patches from weed killer, but it keeps getting worse. My husband attached a grass catcher to our mower, this being the 3rd summer. My question is whether the weed pre-emergence or the grass catcher could be causing the problem or even both of them. I have heard that grass clippings should be left on the ground - also, that the clippings should be raked up.......I hope you can help with my thoughts & concerns.

AnswerDead patches in lawns can be caused by a number of things, from over-application of fertilizers and herbicides, to insects and diseases, and in cold winters, winter damage. Shade is also a factor in how well a lawn grows—grass does not do well in the shade. The type of lawn grass you are growing can also impact how much traffic it can take and how much fertilization it needs. I like to recycle lawn clippings. As long as you are mowing frequently, and not removing more than one third of the lawn grass at a time, you shouldn’t have to bag your grass clippings. The grass clippings can actually add nutrition back to the soil. If the grass gets tall in between mowing leaving behind heavy accumulations of wet grass, then bag or rake, since the clumps of dead grass could damage your lawn, and they are unsightly. Fertilizing every 4 months is a bit odd for a fertilization program. Normally we recommend waiting until the lawn is totally green and then fertilizing. If you grow St. Augustine or Zoysia, you could get by with one application of fertilizer per year, or you could apply one more application midsummer or late summer depending on the amount of moisture we have and how hot it is. Bermuda grass will tolerate fertilizer every month from May through August, but you will mow like crazy, so you may want to only fertilize twice a year. Take a sample of your dying grass to your local county extension office to see if they can determine the cause.


(February 2012)

QuestionWe purchased an older home in North Little Rock that has a beautiful St. Augustine yard. It has increasingly become invaded by a clover-like weed. However, in the past year, we have tried to find a lawn care company to take care of this grass, but after several calls, we have received no takers. I don't mind performing the de-weeding services myself but I don’t know what to use. Do you have any suggestions?

AnswerAs you are aware, St. Augustine is a lawn grass that is quite sensitive to chemicals. There are several formulations of 2,4-D on the market that are labeled for use on Southern grasses. There will usually be a lower rate of application for St. Augustine grass. Remember, it is better to err on the side of too little versus too much. A few sample brand names include: Martin’s DeWeed Lawn Weed Killer for Southern Grasses, Trimec Southern, and Ortho Weed-B-Gon for Southern Lawns Formula II. It may take more than one application to kill your weeds, but spray lightly. If you go to our extension website, there is a lawn calendar for St. Augustine: http://www.uaex.edu/publications/PDF/FSA-6119.pdf and here is the home weed control guide: http://www.arhomeandgarden.org/lawns/Weeds/weed_control_calendar.htm


(June 2010)

QuestionWe live in Mena. Our side lawn was pretty much destroyed by the uprooting of a dozen mature trees by the April 2009 tornado. In November 2009 we replaced the lawn with Zoysia turf. The adjoining front lawn has St Augustine. Bermuda grass is prevalent on all sides at the edges and interspersed in places. It moves aggressively into bare spots. In order to fill in areas where there is still no turf I am encouraging the Bermuda grass. THE QUESTION: Is Bermuda grass the turf of champions as it is so often portrayed or the invasive weed that my wife would like to ban from the lawn so as to protect her gardens? How would Zoysia, St Augustine and Bermuda grass coexist? We both recognize its aggressive nature -I as a benefit; she as a liability. I do not believe that I would be willing or able to ever gain complete control over it, so would prefer to take a "if you can't fight it, join it " attitude.

AnswerBermuda grass is the most aggressive grass when grown in full sun. It is the least adapted to shade. If you have full sun, I would encourage it, since it will grow nicely and would be hard to kill. It will blend in nicely with Zoysia, but St. Augustine is much more coarse in texture and actually doesn't like competition or traffic. I would make sure you keep a buffer zone between the lawn and the flower beds to help manage its spread and keep it from becoming a problem in the flower beds.


(April 2010)

QuestionI have tried and failed numerous times over the years to get either Zoysia or St. Augustine sod to grow on the north side of my home (in the alley between our home and the house next door). My wife and I have decided to consider a ground cover of some type in lieu of grass. Could you possibly point us in the direction of some appropriate types of ground cover for this area which has little, if any, sunshine, year round?

AnswerSeveral choices come to mind, including moss as mentioned in earlier columns. If you want a grass look-alike there is Mondo grass (Ophiopogon) and Liriope or monkey grass--if there are strong borders limiting growth you can use Liriope spicata--the running form, but it can be invasive; the clumping form is Liriope muscarii. Other options include Ajuga, pachysandra, and Creeping Jenny- Lysimachia nummularia--I really like the golden form. Mazus, pratia and ardesia are other choices.


(June 2005)

QuestionI am looking for advice on getting rid of nut grass. I have it in my lawn and I have St. Augustine, which is so sensitive to chemicals. The sprays I have tried are working and digging and sifting is a back breaking job. What can I use in the flower beds?

AnswerNutgrass is one of those weeds that makes moving seem like a good idea! In reality, there are a few products that can give you some control. For the lawn, there are several products labeled for use. One of the best products is Sedgehammer. With heavy infestations you may have to use more than one application. It is one of the most effective products and is safe on all lawn grasses, including St. Augustine and Centipede. The older recommendation is Image plus MSMA. While this is effective on nutsedge, you would have to use at least two applications, and it tends to burn back your lawn fairly badly. It is labeled only for Bermuda and Zoysia. In the flower beds, spot spray with Round-up, but again, it will take more than one application.


(November 2005)

QuestionWhat can I do for my lawn grass at this time of year? The drought we had this summer in SW Arkansas ruined what grass I had left. Ten years ago I had a great St. Augustine grass lawn and now most of it has died. Over the years the ice storms and heat have taken its toll. Can you help me?

AnswerThis is probably not the ideal time to begin a new lawn. The key to growing grass in Arkansas is at least some sunlight and water. St. Augustine is a good lawn for south Arkansas, but it does need water. If you can't irrigate at all, you may run into problems having a great lawn. If you have full sun, Bermuda grass is probably the toughest, and the most drought resistant. Sodding or seeding can be done. Seeding should be from April through early June, while sodding can be done year-round. It will not grow in the shade. Zoysia is another option if you have a bit more shade, but it would need some irrigation to survive.


QuestionHELP!! About 2 weeks ago, I put out 3- 40 lb bags of Weed and Feed. It said it would kill henbit and sandburs and other weeds. Unfortunately, I did not save a bag to see exactly what all it said. Now my weeds are so beautiful and green and nothing is dead or dying. They look healthier than ever. The last two years the weeds have gotten worse and worse and I have got to nip them in the bud. But this has backfired and I have spent a lot of money and still have weeds. I saved an article out of the paper from last year from a lady who battled henbit, (even picked it all out by hand) and your advice to her was to put this stuff out in January, (which I did). I now have green weeds and nothing dying. I am beginning to not care if I have a lawn, just so I don't have weeds. I have partly St. Augustine, which in one part of lawn is so thick; I don't have a problem with weeds. In another part of the lawn there is a mixture of Bermuda and St. Augustine -- that is where the weeds are taking over. I live in the middle of a pasture on 137 acres. Years ago, when we had cows, we sprigged a hybrid Bermuda grass called Alicia. It is great for cows and hay but not for flowers or gardening. It grows 12 foot long runners and when you fertilize your flowers or garden, the Alicia grass just goes wild. So I have mostly gone to shrubs and trees around my house because I like to do other things besides battle grass. The only thing to tame the Bermuda is Round-up. Is that what I must resort to for killing the weeds?

AnswerI wish you still had the bag. Many weed and feed products are a pre-emergent herbicide coupled with fertilizer. Pre-emergent herbicides are used to prevent weeds from germinating not kill those already growing. The product you applied can prevent your summer weeds -- which include sandburs and crabgrass, but won't have any impact on those winter weeds which are already growing. To prevent winter weeds you must use a PRE-emergent in November. As you noticed, you may have actually helped the winter weeds grow with that "feed" portion, which is fertilizer. For now, you can use a product containing 2,4- D -- Trimec is one such product but there are many other brand names. Look for a broad leaf weed KILLER not PREVENTOR. Be sure you find a product that says it is safe to use on St. Augustine. There is nothing that would kill Bermuda without also killing the St. Augustine. Bermuda is a much tougher lawn than St. Augustine, and if you have sun, you may want to convert—giving yourself a weed free zone of mulch between lawn and flower beds. Good luck!


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