The humble man - the one who will find peace and happiness - spends his time looking for the seeds of corruption within himself. Those are pretty much the seeds you have deal with.
Hogg leaves his garden untended, criticizing the gardens of others. Meanwhile, the kid grows more corrupt by the day, and more unable to see that corruption by the day. And of course he gets a helping hand by the evil and ignorant left who pretty much hand out free seeds and will even plant and water them for you.
I'm assuming he said sowed and not showed, sure hope so.