The 39-year-old actor was featured on his fiancee's feed on Monday in a sweet photo of himself holding a lamb. In the caption, Pratt revealed that he actually came up with the words to describe the pic.
"I have often wondered why his hands were so rough. Now I know," the caption read. "He works the farm. He’s a real man."
"Katherine asked me what to write so I wrote the above even though it is not true," added Pratt. "Full disclosure: I have very soft hands. I literally cut my hand today I think, on a lamb. I am from Hollywood. Love, Chris #farmlife."
ET caught up with Pratt earlier this month at the premiere of his latest film, where he explained why Schwarzenegger is his perfect match.
"We're a very blessed family," said Pratt, who shares a 6-year-old son, Jack, with his ex-wife, Anna Faris. "If we could sit here and talk about it, I would tell you all about it."
At a press day for the movie a week earlier, Pratt also opened up to ET about whether he plans to have children with his soon-to-be wife.
"The future? Oh, lots of kids," he revealed. "Maybe less time spent working, more time spent enjoying life."
"I always want to be that guy that works to live, not lives to work," he added. "I think [I want to spend] just a lot of time at the farm and a lot of time catching a lot of fish and seeing lots of sunsets."