You could add a composting system to make fertiliser, maybe it could have many speech marks telling you what to add but only need 1 or 2 of them to make the fertiliser.
E.G. It might say grass and seeds and sticks but when you put one of them in it'll make fertiliser.
It would mean you could make fertiliser no matter what type of plant stuff you have and could solve the scarcity problem late game, without overloading players early game.
#Fertiliser
empty oar
lime moat
This is already in discussion and within the community poll 😅