Frost??? Hey, it's semi-tropical here... Palms and banana trees grow here... But seriously, maybe an inch... I'm pouring 6 inches... The Kabota with that tooth bar will dig about a foot... Lifts the front wheels a foot or so off the ground to bust thru what H-man described as red concrete... It's more like a softish brick concrete but tooth bar goes to war with it... The hardest part is shoveling it out after the Kubota + tooth bar have had their way with it...