The Ferti-Lome Weed Out with Crabgrass Killer does not specifically state that it will control St. Augustine grass, however, it does advise, “Do not apply to St. Augustine turf” as it can cause injury so it is possible it would kill it.The label also advises that application to bermudagrass may cause temporary yellowing or discoloration but full recovery can be expected. Do not apply to bermudagrass when daytime temperatures exceed 85° F.
We recommend that you spot treat the St.Augustine with a non-selective glyphosate product such as Roundup Quick Pro and then resod with Bermuda.
Ferti-Lome Weed Out with Crabgrass Killer will not prevent crabgrass from germinating but will eradicate crabgrass that is actively emerging/growing but not past mid July as the crabgrass will be too mature and more difficult to eliminate. Please contact your local cooperative extension office for specific timing in your area. We recommend that you apply a pre-emergent herbicide such as Prodiamine to prevent it from emerging.
Ferti-Lome Weed Out with Crabgrass Killer should not be sprayed around the knock out rose bushes (and other ornamentals) and not on exposed roots. You should also not use the clippings from treated areas to mulch around landscaping etc. You may need to spot treat those areas with a non-selective like RoundUp or manually remove the weeds from that area so the bushes are not harmed.
The rate for Ferti-Lome Weed Out with Crabgrass Killer is 6.4 oz. per 1,000 sq. ft in 0.5 to 1 gallon of water. For an acre you would need to use approx 22 to 44 gallons of water with approx 281.60 fl oz of product.
Yes Ferti-Lome St. Augustine Weed and Feed 15-0-4 would be the equivalent product for St. Augustine grass. This should be applied in early spring to prevent crabgrass, paspalum, spotted spurge, and sedge; and then again in the fall to avoid winter weeds like evening primrose, rabbit tobacco, henbit, and chickweed. Check the label for a number of other weeds that Ferti-Lome St. Augustine Weed and Feed 15-0-4 will control. Remember to water in Ferti-Lome St. Augustine Weed and Feed 15-0-4 after application.