On our windowsill we have a two week old custard apple fruit growing on a plant which doesn't look strong enough to take its weight. Three years back, the plant was in a seed which my son planted after consuming the fruit. I never expected it to germinate, much less to bear fruit. But against all odds, it did. I know the birds are unlikely to let us taste the fruit, but who cares? We have a fruit-bearing tree.
What's amazing is that none of the saplings we bought survived. Who can tell what will take root and what wouldn't?