So I have a gardening sim, with an inventory and fridge full of multiple veggies and fruits and what not else.

But unless a stack size is one, you can't tell what quality of ingredient, you simply see '14 onions' or such.
Basically, what we're asking for is a more visual indicator on the icon of fruits and veggies themselves to tell their quality. For example, maybe coloring the icon border:
Grey: Rotting
Red: Kinda bad
Yellow: Poor
Green: Average
Bronze: Nice
Silver: Very Good
Gold: Great
Maybe that, or a number of stars (pips) on the icon, anything.

I can't really stand having to pick apart a stack of 24 onions to find out which are Great and which are Average.... because the Average ones get used as fertilizer.
Comments
keeping all my apples in a stack is most convenient.
by clicking the group expand (tear off in the upper left of inventory icon) you can see the contents of the group, it will sort them from best to worst for you.
it makes finding what you are looking for fairly quick while reducing the number of base inventory slots consumed.
Perhaps the ability to move all of a particular quality of item out of a stack would help here as well. beeing able to seperate my best apples (or w/e) and sell all the rest for example.
a stack of apples of all varieties in your inventory, expand to a window including stacking of specific qualities. why do we need to see individual items of the same quality when we can drag one at a time from the stack anyways.