We see Ozzy Osbourne singing the classic Black Sabbath song: “Sweet Leaf” as he tends to a few pot plants in his private greenhouse. He sings the part just before the second verse to the plants, as he waters them (“I love you, oh you know it!”), and then he sings the second verse as he prunes the plants. The announcer chimes in, saying Miracle Gro helps all your plants grow up to be the strongest possible. And then the original recording of “Sweet Leaf” starts playing from the part where Ozzy sings: “Come on now, try it out!” (This time over a product shot of Miracle Gro, and meaning to try out Miracle Gro.) and then the music fades out before the last verse begins.
This is “Sweet Leaf” by Black Sabbath (The part I’m referring to starts at about 1:30):
(You never know: once pot is legal in all states, maybe they’ll make this ad for real. And it wouldn’t necessarily have to be Ozzy singing it either: it could just be some metalhead stoner guy. And it doesn’t even have to be pot plants if Ozzy is in the ad: it could be any plants; and in that case, they could make the ad right now.)