The growing seed – Mark 4vs26-29

Mark 4:26–29 (NIV):

The Parable of the growing seed

26 He also said, “This is what the kingdom of God is like. A man scatters seed on the ground.
27 Night and day, whether he sleeps or gets up, the seed sprouts and grows, though he does not know how.
28 All by itself the soil produces grain—first the stalk, then the head, then the full kernel in the head.
29 As soon as the grain is ripe, he puts the sickle to it, because the harvest has come.”