Though it sounds like a party for a yuppie gentlemen farmer to show his friends the acre, the cow, and the carbon-neutral construction bamboo and mahogany barn, a "farm warming" is in fact just a code name for a big gay sex party. Usually the attendants are pretty much the same people who would be at an actual farm-warming, and it can occur in a carbon neutral barn structure.
"Spencer and Jack never came home last night after that 'farm warming' they went to -- I guess all that plowing tired them out."
"Either that or the huge amounts of gay sex."
"Yeah, one of those."