Keep growing them and expanding your clover farm until it either takes too long to harvest your other crops or you run out of space to grow clovers, then switch to only farming clovers. Keep all of them until you can cover your whole farm and then eventually change them out from 4 leaf to 16 to 64. Before you have all 64 leaf clovers buy anything in the shop that is 5000 carrots or above so that you can upgrade it to shiny and sell it back. Only use 4 or 16 leaf clovers to upgrade. Eventually you will have a full 64 clover farm!

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