Per the product label: Vexis Herbicide Granular Label 2lbs per 500 sqft is accurate.
According to the label, Vexis Herbicide Granular you should wait until the second mowing to apply to new sod or seeds and 3 weeks after application to seed or sod.
Vexis Herbicide Granular is labeled to use on established Zoysiagrass.
It is best not to apply products until your lawn is well established, which typically means that it has been mowed at least twice. Per the Vexis Herbicide Granular Product Label: "Delay application of this product until 3 weeks after sodding, sprigging or plugging operations".
Per the Vexis Herbicide Product Label: Do not apply directly to flowers, vegetables, ground covers, gardens or landscape plantings including ornamental shrubs or trees. We would not recommend using this product in flower beds, this is strictly to be used in your lawn.
How to Calibrate your Spreader
https://www.youtube.com/watch?v=9vXBjeVA3ao&list=PLG-iVFWQzYnkrUznseZ-SDTcWgflq8DDo&index=39
Vexis Herbicide Granular is not labeled to control clover. Clover is best treated when it just emerges as once it flowers it is almost impossible to kill. Atrazine is always on an option for St Augustine. Weed Free Zone is another option if you do not have floratam or bitterblue variety. Depending on the type of clover you have a pre-emergent like Gallery is a great option to prevent it coming up. We also have helpful guides here that can help.