Junwang explains that it means crouching down in the paddies and using your hands to squash the wild grass down into the soil where it will expire from lack of sunlight. This can also stir up and circulate the nutrients in the soil, so the stalks will grow faster.
阿旺解釋，就是蹲在田裡用雙手把雜草壓進土裡，讓雜草無法行光合作用；這個動作也可以把田裡的養分翻動上來，稻穗長得較快。