"In autumn ten thousand grains are harvested" is often cited to describe the return on farming.
Tips
history
From Li Shen's (李绅, Tang dynasty) 《悯农二首》其一: 春种一粒粟，秋收万颗子。四海无闲田，农夫犹饿死 — 'In spring one millet seed is planted; in autumn ten thousand grains are reaped. Within the four seas there is no idle field, yet farmers still starve to death.' One of the most politically pointed Tang poems — memorized in every Chinese elementary school.
usage
Almost always cited with its setup 春种一粒粟. 颗 is the measure word for small round things (seeds, pearls). The strongest rhetorical force comes from the ironic third and fourth lines about farmers starving.
