That product is made from baking soda, cinnamon, and a few other spices that make it look like a cake recipe gone bad. According to the container the cinnamon is the active ingredient. However, according to other sources in Florida, the active ingredient is really the baking soda.
With that in mind, I posted a challenge on another forum for someone to try it. One guy went beyond the call of duty and posted pictures of his results. They were spectacular! In a St Augustine lawn, the crabgrass turned black and died overnight leaving the St Aug 90% untouched. The next day all the crabgrass looked like straw and was laying flat on the ground. I was expecting good results but not that good.
The approach I suggested for applying it was to start by learning how to wet the surface of the crabgrass blades. Crabgrass blades repel water but with soap and molasses, they can be wetted. The guy used 2-tsp of soap, 1-tsp of molasses, and 2-cups of water. Then I suggested putting the baking soda into a sock as an applicator. After spraying the crabgrass, he applied the baking soda by beating the sock between his hands. This technique allows only the lightest dusting of baking soda. When the moisture dried the crabgrass was frosty looking with baking soda. Then in two days it had turned black and wasted away!!