I have a CYV, so the landscaping is not extensive, but it's all rocks since we had the grass removed. I use Spectracide Ready-to-Use 1-Gallon Weed and Grass Killer. It's $7.98 with sprayer at Lowes in Trailwinds on 466A and their website said they have 343 in stock. Kills the weed in 3 hours or less, and it works everytime.
https://www.lowes.com/pd/Spectracide...ler/1000373169