My Papa posted on Facebook that he’s growing lettuce. I think the whole point of the post is to demonstrate not lettuce farming (because what would you do with lettuce, my fellow inebriates?) but rather the balmy weather we’re enjoying on the west coast. But just in case, I searched DrinksMixer for cocktails involving lettuce.
Nope. Lettuce is useless.
Liquorstore Bear 
Lettuce is that green stuff you sometimes find in sandwiches, right?
My mother still believes in the white lunch theory: white meat with mayonnaise, served on white bread. Including a side of milk and potato chips. It’s why I cook when I’m home.
Your dad has time to garden, work, parent, and write a novel, but not drink? Hmmm, are you sure it’s actually lettuce he’s growing?