There are lots of quests on earth(prestige and daily ones) that we need farm wheat. The prob is that those quests take ages to do because when you break more than 1 at the same time it doesn't count i think that should be fixed.
I suggest opening a ticket. Please make sure to select the earth gamemode and "bug report". If that doesn't help, please let me know on discord so I can help you out. JASO0ON#6804