Celsius WG is labeled for post emergent control field sandbur. Please view the product label for more information.
With Bonide DuraTurf Crabgrass and Weed Preventer for Lawns and Ornamental Beds being a pre emergent you want to apply it when soil temperatures are below 55, generally done in Fall & Spring.
Please view our Lawn Care Schedule and or contact your County Extension Office for help with timing.