How long does Blackberry Bush Killer transport to work? Just wondering how long it will take for this stuff to work....

Just wondering how long it will take for this stuff to work. I used it on a 1000 sq foot area jam-packed with blackberry bushes. I used LillyMiller Blackberry Bush Killer (with a hose) - the weather has be dry for the last 3 days and will be for the next 3 days.
Planting elephant ears?
Answers:    I haven't have to do this, but as they aren't super fast growers I would say they will be slower to die than utter a weed or grass. I wouldn't expect to see any change at all back about 10 days, (if it is summer where you are) but I am definately no expert!