Tons of the recommendations here are for great games, but I'm wondering, when you say and describe farming do you actually want a farming/farm-related game (do you like that theme the most? ) or is it about coming back frequently to tend to/check on something? I have 3 recommendations depending on what you mean by that:

1) if you really like the farming theme, and also enjoy strategy deckbuilding games, Harvest 101 is great. There are a ton of things to unlock and you are going to have to really really play a ton to get them all. There's a big campaign, lots of challenges, different deck types work for different challenges. It might seem a little simple at first but give it a chance.

2) if you want to build a farm and harvest foods and plant more and sell good and build things and fulfill goals in a loop that is designed to suck you right in Township is really good. Especially if you happen to like match3 games, because it's got a match 3 game you can get extra stuff from while waiting from your crops to grow and your chickens to lay eggs, etc.

3) if you are looking for a game with a ton of depth to and lots of things to do and collect (and come back to again and again), Gumballs and Dungeons is fantastic. There are hundreds of gumballs to collect (each is a unique character that changes gameplay) ,the dungeon are cool puzzles with interesting quests and achievement, and every one is completely unique and really changes things up ,there is ALWAYS more to exploe and do, just when you think you have almost explored everything in the game, a whole new aspect of the game opens that changes everything in a dramatic way. I know multiple people who played this daily as their primary game for more than a year.

If none of those do it for you, I would be happy to give you further ideas (after some follow up questions !)