Micky from Edmond Ok writes
The Tower Herbicide is a pre-emergent herbicide that would normally be applied either in the fall or spring for control of listed weeds/grasses. However every region across the US has a different time frame on when you need to have a pre-emergent down by in order to get the control you are looking for. We recommend contacting your local Master Gardener or Cooperative Extension Office to find out when the time frame is for this type of application in your area to see the best results.
Answer last updated on: 09/14/2013