I have observed that plants like an onion or spinach, after having been harvested for their leaves, will continue to regrow their leaves.
My question is how many times can we keep regrowing them with good amount of production (i.e. not too low than the first harvest)?
I am told that it works only for few harvests (~2-3). But why so? If I 'feed' them well in a an optimal setting, can we get to regrow them for many more harvests?