I like the game, in particular the style with graphics, sound effects etc. Things I think would be good to add:
1) "Sell half" button, especially for crops
2) I think there could be buildings to house each kind of animals. At the very least, the donkeys who don't require any clicking. Same with clouds and storage - they take up a lot of unnecessary space in the user interface. One icon for storage, one for water storage, one for donkeys should be enough.
3) Something to interact with. It could be for example a market that lets you buy things for a higher price than you sell for - it could also be affected by what you sell/buy. Or you could have a neighbour farm to compete with - that'd clearly take it out of the idle category and more into the strategy realm.
Of course, extensions in all directions are possible. "Tech tree", leveling up, missions, events, cards...
Nice game! Would it be possible to have an option of one or more computer-controlled rival Tangerine players? At first, they could buy bushes and labs and so on, like the player. Later, perhaps you'd want to add interaction with them.
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 "Tangerine Tycoon"){kind=icon}
 "High Tea"){kind=icon}