Help me get rid of my St. Augustine Grass!!!

Help me get rid of my St. Augustine Grass!!!

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mark_shiffer – posted 05 March 2001 12:10

Does anyone have any good ideas on how to get rid of my St. Augustine grass?

I live in Austin, TX where we get a fair amount of rain usually, but I let the drought last year kill off as much of the lawn as it could because I cannot stand the horizontal growth of St. Augustine grass.

I have read some and thought zoysia might be a good choice, but can I overseed the St. Augustine with this, or do I need to till the lawn and prepare a decent seed bed for it? Will it even grow well in Central Texas? It seems everyone around here has Bermuda or St. Augustine…

Any help would be greatly appreciated.

seed – posted 07 March 2001 10:49

Mark, it’s fairly easy to kill St. Augustinegrass with Roundup herbicide. Just follow the label, and make sure that the St. Augustine you want to kill is in a green luxuriant state of growth.

Your other questions do not have such easy answers. Zoysiagrass is a promising grass in many of the transitional areas between the cool-season grasses such as tall fescue and the warm-season grasses such as bermuda and St. Augustine. But promises and realities are two different things. For one thing, zoysiagrass seed is not commonly available commercially, and even if it were, you would need to prepare a good seedbed. Whatever you plant, you do not necessary need to till the ground unless it is compacted, but you do need to remove the debris to get good contact with the soil, and sometimes tillage is an unavoidable necessity just to get the surface layer of soil worked up.


mark_shiffer – posted 07 March 2001 12:23

Last year during the drought, I refused to water my lawn for two reasons: 1. The Drought and 2. I hate St. Augustine grass (The sideways growing, hard grass), and figured why not kill it off then plant new grass.

I should have thought ahead in the process, but here I am dealing with the aftermath. I have a 90% dead lawn. Most of what is alive are weeds. My idea was to start anew.

From what your saying though I should probably Round-up the whole lawn to kill all weeds and what is left of the grass. Then till the remnants under and plant, right?

I have found zoysiagrass seed available on the internet. Anyone know about the viability of zoysiagrass in Central Texas weather?

seed – posted 08 March 2001 12:14

Mark, please post here a web address for the zoysia seed, so we can all check it out.

Yes, when you intend to kill your St. Augustine, it’s best to start with the most powerful tool first, and that is Roundup. It’s not too late to use it to clean up the aftermath, but I remain concerned about the possible escape of underground rhizomes of weeds.

Here’s a 7-step guide to establishment of turf:http://grove.ufl.edu/~turf/turfcult/97/estab.htmThe 7 steps are represented by the letters PEGISID:

PLAN for the uses, environment, and maintenanceERADICATE noxious weeds with Roundup, etc.GRADE the rough contour, including remove debrisIRRIGATE, install or renovate the irrigation systemSEEDBED, do a final smoothing if the soilINSTALL, plant whatever turgrass you needDEFEND, against drought and weeds


Rose – posted 12 April 2001 17:57

Seedland.com has zoysia – $25 per pound. Here’s a link to the “buy it” page: http://www.seedland.com/cgi-bin/miva?Merchant/merchant.mv+Screen=CTGY&Store_Code=Seedland&Category_Code=ZOY

rubby – posted 21 January 2003 01:21

I live in Sacramento and I tried Roundup, purex, water softener salt, boiling hot water, and digging my entire front lawn up! Nothing has killed the st augustinegrass! The nursery people don’t know what will kill it either. I have spent 5-years trying to kill this grass. It is coming through and under the fences. It is brown now, so I star again every winter alternating salt(which slows the growth down) then vegetation killer. It still creeps over the salt and returns. Easy! Puppy Cock!

Will-PCB – posted 21 January 2003 22:49

Well hell. I kill my St. Augustine grass routinely (by accident of course). Its the damn weeds I have trouble killing.

Interesting that I was plush St. Augustine and hurt it constantly (requiring replugging areas frequently), yet you want to irradicate yours, and cant.

Murphy’s Law rules in Lawn Maintence.

forrest – posted 02 March 2003 23:31

well shucks, her i was, all set on finding(somewhere-this is california and no one seems to transport st. augustine) this stuffand now I’m thinking to take a second look.I have pet pigs and chickens, though; they really do a number on conventional grass, even bermuda grass seems to be losing thebattle. Anyone has suggestions?

ted – posted 04 March 2003 21:50

i can’t believe some of the advice on this board…

first of all, why do you want to get rid of the st. aug? it’s a perfectly functional grass for the area! people generally don’t like it because they’re too lazy to weedeat, since the grass sends runners out into the flower bed. both bermuda and st. aug. will work in austin, but if you’re itching to use zoysia don’t use seed!!!! you’ll have to wait until the st. aug. is back and strong again ( and it will be) then around say may or can use 46% professional strength roundup ( buy it at lowes) and spray the lawn at 2.5 ounces per gallon on your backpack sprayer. you may have to do it twice. then after it’s dead, yank up all of the sod, and resod with zoysia, make sure you’ve smoothed out the soil first, then lay the new , fresh sod. there’s alot of stuff online about zoysia, probably texas a and m has alot of info or you could call their extension office. better yet, why not call a local reputable landscape company???? you might try calling your local lesco service center , as well. sorry for the gripy comments, but there’s so many people going around beating their heads against the wall, and so much crappy advice, it’s unbelievable..

a chemical lawn care company owner in houston

keygold@aol.com – posted 21 June 2003 09:55

i want to kill zoy grass badly…do not want to sterilize the soild….how about an inch of newspaper under several inches of bark and allow to turn into mulch???????please advise rush…penna is very wet this year….zoy grass is now green and looks nice, but it is yellow and looks dead most of th time….7-8 mos per year…good weed killer…but, it keeps spreaduing./…..we hate it

help…bob greene keygold@aol.com

crid – posted 27 June 2003 21:34

The organics are coming. They are superior. They are easy. And most of all, it’s the right thing to do. Check it out.

Dchall_San_Antonio – posted 27 June 2003 23:30

I’m just south of you in San Antonio. I remember when I came from the land of vertical growth grasses (Dayton, Ohio), I had a little trouble getting used to St Augustine, too. Now I love it. The way I’ve heard most people killing their St Aug (accidentally) is by smothering it with compost. So you might try mulching it with at least an inch of anything you have handy.

AJ – posted 30 July 2003 13:30

Mark, I live just outside Austin. When I build my house the builder gave me a choice of St. Augustine or Tif Bermuda. I chose Tiff Bermuda because I have rather large lot wanted less maintenance. I love this grass. It is a slow grower, doesn’t need to be mowed as often, it is softer and darker green than St. Augustine. Some neighbors cut it short like a putting green. The most amazing feature is that it isn’t as invasive as coastal bermuda. I have plastic edging around my flower beds and it rarely crosses it. I have seen adds for El Toro Zoysia for Austin, I looked into zoysia but it is very expensive. For info on turf grasses check out the TAMU web site for Aggie Horticulture.aggie-horticulture.tamu.edu/tamuhort.html

My problem if someone can help is that my neighbor has St. Augustine and it is invading my Tif Bermuda! How can I kill the St. Augustine without killing my bermuda?

Dchall_San_Antonio – posted 31 July 2003 08:42

AJThe only way you’re going to be happy is to put in a 4 inch wide and 4 inch deep border between your two lawns. If you do it soon, you can pull out all the St Augustine. Or you could put in a ground cover between the two. You might ask your neighbor if he’d be willing to go halfseys on either of the two. He might be willing to share a common ground cover like Asiatic jasmine. You’ll both need a steel border to contain the jasmine because it can be invasive, too. But with a border, it works great.

I have both jasmine and a 6 inch wall between me and my neighbor. Trimming is pretty easy.

BermudaDallas – posted 09 August 2003 18:00

MSMA Crabgrass killer will kill St. Aug. w/o hurting Bermuda-good luck!

VooMan – posted 10 August 2003 23:04


I’m with Dchall on this one for sure… I had concrete border curbing installed last year and it was one of the best investments I could have ever made in my yard. I edge the bermuda just like I do along the sidewalks, and it never gets across the border to invade my flowerbeds. It’s four inches wide and deep, and it works wonderfully. 🙂


[This message has been edited by VooMan (edited 10 August 2003).]

Lex – posted 24 August 2003 08:18

Just kill the St. Augustine (or zoysia) with Roundup. The active ingredient is rapidly broken down in the environment once it hits the soil (I manage a major environmental organization and worked in pollution prevention for years). You’ll do more damage to the environment driving back and forth to buy the chemical than using it.

Why get rid of St Augustine? Lots of good reasons. St. Augustine requires more water (water is an issue in San Antonio and much of TX), it makes the kids itch, could be renamed “chinchbug bait”, and atrazine is about the only reasonably priced weed killer that won’t kill the grass. Atrazine is persistent and is slowly getting into water supplies (some extreme environmental groups are calling upon EPA to ban atrazine or greatly restrict its use). Zoysia and bermuda require less chemcials and less frequent cutting (most varieties).

Dchall_San_Antonio – posted 25 August 2003 10:08

quote:Why get rid of St Augustine? Lots of good reasons. St. Augustine requires more water (water is an issue in San Antonio and much of TX), it makes the kids itch, could be renamed “chinchbug bait”, and atrazine is about the only reasonably priced weed killer that won’t kill the grass. Atrazine is persistent and is slowly getting into water supplies (some extreme environmental groups are calling upon EPA to ban atrazine or greatly restrict its use). Zoysia and bermuda require less chemcials and less frequent cutting (most varieties).

I want to respectfully disagree with a couple (not all) points made above. St Aug does not have to be a water hog. My next door neighbor has not watered her lawn for 4 years which have included some pretty good droughts. It looks pretty darned good all year round. The difference is she trained her grass roots to go deep looking for water. We are not on deep soil, either, so they don’t have to go very deep.

Then skipping down to the bottom, the only reason zoysia doesn’t need to be cut often is it grows so fricken slow. Of course it grows pretty short even when left alone, too. And bermuda should be mowed weekly for the best appearance and softest touch.

I must be more allergic to bermuda because that stuff makes me itch.

Now to go back to the middle of the message above, when properly cared for, St Aug will choke out most weeds. I just got back from Port Aransas, Texas where I saw St Aug invading the dunes, growing unmowed at about 30 inches tall, and as dense as you could imagine. It is taking over all the grasses and forbs in the dunes. So my point here is that you might not need a weed killer in St Aug when you do the right things.

[This message has been edited by Dchall_San_Antonio (edited 25 August 2003).]

Alex_in_FL (Lex) – posted 08 December 2003 16:46

Please feel free to disagree! I think St Augustine is wonderful… especially in your yard, where you mow it, you edge it, you fight the chinch bugs, and you itch if you play with your kids in it!

As a *general* rule St Augustine requires more water. I am stingy with water to encourage deep roots. So far I have noticed that my floratam usually needs watering before my zoysia even though my zoysia is not yet 2 years old. And I water far less than my neighbors.

My zoysia needs cutting about everyother time I cut the floratam. This suits me! More time to play with my kids, swim in the pool, or even play a round of golf.

Again, feel free to disagree!! I think those of you that prefer mowing grass to playing should fertilize often and water heavily!!!

Happy mowing!!!!!

nohow – posted 03 July 2007 17:09

St. Augustine is the best,install sprinkler system with timer, water for 10 minutes each morning, fertilize twice a year, hire a Gardner! Results = an excellent lawn that neighbors will envy, kids will enjoy and free up every one of your weekends for fun!

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