A proverb meaning you won't get results unless you put in effort — 'you reap what you sow' / 'seeds you don't plant won't grow.'
就職したければ応募しないと始まらないよ。蒔かぬ種は生えぬだ。
If you want a job you have to apply. You won't get results without sowing seeds.
練習しなければ上達しない。蒔かぬ種は生えぬと先輩に言われた。
If you don't practice you won't improve. A senior told me, 'you reap what you sow.'
何もしないで結果を望むのは無理だ。蒔かぬ種は生えぬということだ。
It's unrealistic to expect results without doing anything. That's what 'you reap what you sow' means.