stone said: ...
There are also people that will insist that there will be problems with stuff robbing the soil of nutrients while it continues to break down.
I think that refers to "nitrogen deficit", which can occur if you MIX too many "browns" INTO the soil, and they can break down quickly. For example, sawdust and chopped paper are "browns" (high-carbon and low-nitrogen) and they can break down quickly.
All that "C" (carbon compounds) being release quickly promotes rapid growth of soil microbes, which then need a balancing amount of "N" (nitrogen). Of course the soil can't provide THAT much N instantly, and the microbes are MUCH better at sucking up N than plant roots are. So the plants have almost NO access to N until the soil microbes finish digesting all the excess "C".
If grapefruit rinds had almost NO nitrogen, AND they were finely chopped, AND they broke down quickly in soil, AND you turn them under, you MIGHT get some N deficit. But I would have guessed they were pretty neutral, having some N to balance their C. And I think they break down slowly, being rinds. And you didnl;t chop them very finely.
But mainly, if you do compost them first, letting them rot until they look more like soil than like garbage before mixing into the soil, there won't be any nitrogen deficit.
I also screen my compost before adding it to soil (either on the surface or tilling it under). The people who "sheet compost" or compost on top of next year's garden beds, do get more value from the scraps into their soil, because none leaches out and gets lost away from their garden.