Blocks with different growth stages

a cool feature to have would be blocks with different growth stages. such as plants and crops like wheat, carrots, potatoes, or beetroots. the ability to tell it how many ticks to wait until it grows for each stage or have it on a randomizer. or even multi-block height stages so you could grow 2 block tall growth stages for use of a theoretical crop of corn that would be taller.

these would automatically grow on farmland of course, but giving the option not to would make it even better. like the side of a block like cocoa beans on trees for example.

I know it's possible to do this kind of thing as a procedure, but it looks very complex to a noob such as I.