Yes, Dimension 2EW Herbicide can be used on St. Augustine grass. Please review the product label for complete application instructions.
If using Dimension 2EW Herbicide as a pre-emergent application, no surfactant is needed. If you are using Dimension 2EW Herbicide for post emergent crabgrass control, the product label calls for non-ionic surfactant, such as Hi-Yield Spreader Sticker Non-Ionic Surfactant.
A surfactant, also referred to as wetting agents or spreader stickers, help your liquid lawn and garden products adhere to, or "wet", the foliage they are sprayed on, ensuring you get the most out of the products. Pre-emergent herbicides are applied with the goal of the active ingredient working it's way down into the soil in order to target weed seedlings to disrupt the germination process, so it does on emerge from the soil.
Yes, Dimension 2EW Herbicide is labeled for controlling sandbur. Please review the product label for more information.
In Arizona, you would generally make two applications of Dimension 2EW Herbicide 5 to 10 weeks apart. We would recommend the Program 2 or 3 rates of 1 oz per 1,000 sq ft and then 1.5 oz per 1,000 sq ft, or 2 applications of 1 oz per 1,000 sq ft each, according to the product label. Be sure that you immediately water-in the application with a high volume of water any time there is a barrier like gravel over the ground. This will help get more of the active ingredient down to the soil so that it is not just absorbed into the rocks before it can reach the dirt. (Since this product is still intended to be used around turfgrass and ornamentals, you may not get the same results on a stone area.) At the 1 oz,1000 sq ft rate, you would use 0.22 oz of Dimension 2EW in 1 gallon in your sprayer to cover 220 sq ft. Please confirm with your county Master Gardener at the cooperative extension office for specific timing of application.
Barricade and Dimension are actually in the same class of herbicides which means they work with the same mode of action for most of the same weeds and there would be no benefit to using each so close together. It is more recommended to rotate each season between different actives to prevent resistance buildup. Typically Dimension is more recommended in the spring as it is best for crabgrass and has early post emergent control of it as well (in a separate application). Using the max rate in one season would prevent you from using either in the fall which is also a recommended time for pre-emergent applications for winter/spring weeds.
We would not recommend applying herbicides such as Dimension 2EW Herbicide during active precipitation or after rainfall. The manufacturer recommends to water this product in within 24 hours after application, so it would be best if you apply it the day before rain is expected again if you do not manually water the product in for pre-emergent applications.
Yes, if you have used the maximum rate of prodiamine for the year you may use Dimension 2EW Herbicide since they are two different actives. You can either spot treat or blanket spray. We would recommend blanket spraying as it would give you better results for pre-emergent control.
Dimension 2EW Herbicide is labeled for brome prior to germination when used as directed.