Who planted the wheat?

Jonesy planted it

Good question never answered. I'll go with the engineers or whatever those people were. The reason I say it was those people is because they were on the planet before David and Shaw. They have to have food resources on the planet unless they are cannibals and breed babies for food.

It must have been the "human-like" engineers. 

Scott and Fassbender have stated in several interviews that David and Shaw lived together for a while on the planet. I'm guessing that Shaw planted it. She obviously scavenged the wreck of the Prometheus before leaving in Juggernaught. Maybe some wheat seed was in the stores for some reason, and she was able to grow it on Planet 4 before meeting her demise. Just one of the MANY questions unanswered in that movie!! I hope we find out everything in Awakening.

I'd say the Engineers...Wheat is probably their crop...And they brought to Earth thousands of years ago. So wheat is alien food.

David planted the wheat to feed Shaw and her clones.

Dr. Curt Connors, I wasn't born yet.