The above best-case loop loses one glazenut each time, so it'll run out of gas eventually. The only way to have a truly self-sustaining plot is to make as many glazenuts as you're putting in. If you're putting in 8 seeds (4 for the glaze+apricot and 4 for the glaze+lemon) and only getting, at best, 7 back (7 from glaze+apricot), then you're going to run out. Granted, it takes while to run out and this is certainly the most efficient use of glazenuts to get more glazenuts, but self-sustaining it is not. The apricot side is self-sustaining, yes, because you're only using 4 apricots but getting 4-7 back.