Let's Talk Weed Killer !!!
 

I have a St. Augustine lawn now that has spots begging for some weed killer. I do my own lawn and want to get on this before it gets out of hand.

My question is this "Does anyone know what weed killer works best on St. Augustine grass and where to buy it ?

Thanks for the read and any help offered.

Scotts weed and feed?

For spot treating:
Round Up for southern lawns
https://www.lowes.com/pd/Roundup-Sou...SABEgJkVfD_BwE

Doesn't 24D work on this grass?

Ace Hardware has a house brand weed & feed for southern lawns. DO NOT use this on St. Augustine. I learned the hard way. Be sure to ask! Massey saved my yard!

Products containing 24D such as Scott’s Weed B’Gone will kill the St.Augustine grass variety that is planted here in The Villages. The variety planted here is Floratam and it is mentioned in the product label as not to be used. Might I suggest you visit one of the Master Gardener clinics either at the Villages Annex at the intersection of Morse and 466 on Monday 9-3 or at the Sumter County Service Center near the Village of Pinellas on Friday 9-3. You can kill your lawn if you use the wrong product. 24D will kill the St. Augustine grass planted here in The Villages.

Keep 'em coming
 

Thanks for the replies. I really appreciate the info. I'll make the trip to lowe's and get a jug of Roundup for weeds and see what happens. I already feed my lawn myself so the Weed N Feed would be over-kill.

Please keep the comments coming... :laugh:

Amazon sells a Roundup concentrate that is for use on Southern grasses including Floratam and Centipede.

Amazon

You should find answers on the internet
 

We have the EMPIRE ZOYZIA. Someone mentioned 24D. Like so many others, we've had our gardener of the people used by our neighbor pick up pieces of St Augustine and introduced it into our lawn. The St Augustine is less able to take 24D but to kill the St Augustine in my Zoyzia lawn I need to do everthing in the instructions wrong. Allpy it on a hot day and mix it at double strength.

I DO NOT USE ANY OF THE WEED AND FEED PRODUCTS.
I use liquid weed killers and spot treat weeds with a simple windex reused bottle. Any granular WEED AND FEED typ product. The weed killer needs to stick on the plant leaves, the fertilizer needs to get to the soil. The insturctions oon fertilizer say to water it in to keep it from buring the leaves. A weed killer-it says to apply on a dew wet lawn so that it sticks to the leaves.

Also, all the WEED and FEED products that I've seen are far higher in Nitrogen then is recommended for my empire zoyzia and I think that is true for the posted St Augustine as well

A great way to apply stuff like liquid weed killers with out killing you bushes etc. Use a paint roller.

ROUNDUP And Cancer
 

....Monsanto Weed Killer Roundup Faces New Doubts on Safety in Unsealed Documents - The New York Times

Scotts bonus S. Its the best for St Augustine

I got a nice broad leaf kill on a St. Augustine lawn earlier this year with a split application, 7 to 10 days, of Trimec, and a bit 80/20 surfactant. I think the Trimec came from Tractor Supply in Leesburg if you cant find it locally.

Re: Trimec
 

First of all titles are deliberately misleading. In my view the reason is so people-wholesalers-retailers san MISLED the buyer to claims ours is better than theirs. If, you read the label you will find your trimec product is just another name for 24D. The 24D was discovered, invented by the British for WWI (1918) so it is long out of patent.

As to effectiveness, the weather is very important-rain will wash it off. Zoysia is more tolerant to the broad leaf weedkillers (24D) than is St Augustine. If, you apply 24D to St Augustine ON A HOT DAY, it could well kill your lawn.

Applying every 7-10 days-depending on the type of weed you are killing or attempting to kill it can take about 2 weeks for 24D to work.

A secret that no licensed guy can tell you if they know.
If, you have a zoysia lawn being invaded by St Augustine,
you can mix 24d extra strong and it will kill St Augustine and hopefully not the zoysia. Do it in a spot to try it.
Don't blame me if it doesn't work. My rule-do not overdo anything. You can do things again you cannot always undo what you have done.

DO NOT use Roundup on St Augustine or Zoysia. It is a non selective herbicide, i.e., it will kill every thing it comes in contact with. Use atrazine on St Augustine for weeds.

Made for use on Floratam St. Augustine
Shop Roundup Southern Lawns 1-Gallon Weed Killer at Lowes.com