How do I grow sabja seed cleanly and harvest it without losing the tiny seed?

Sabja heads mature unevenly, so the practical method is to harvest when most of the spikes on a head have dried and turned brown, then dry the heads further and thresh gently so the small seed comes out without crushing. Because the seed is light, clean it carefully with sieves and gentle winnowing to remove leaf and stalk trash, since buyers want clean, uniform, dust free seed. Dry the seed down to safe moisture before storing, because damp sabja develops mould and a musty smell that gets it rejected. Avoid harvesting in dew or rain, and handle gently to keep the seed coat intact, as broken seed loses value. Clean, dry, well graded sabja fetches the better price, while trashy or damp lots are cut or refused.