But when the fruit is brought forth, immediately he putteth in the sickle, because the harvest is come.
Note 2 at Mr 4:29: In most instances, when grains, vegetables, or fruits are ripe, they must be harvested immediately (i.e., within a matter of days). If not harvested quickly, grains will fall off stalks; be consumed by birds, insects, or rodents; or become moldy in humid weather. Fruits and vegetables will either rot, dry up on the vine, or be consumed by insects and birds. A very productive harvest can be totally destroyed if it is not harvested at the right time. Only God the Father knows the precise moment when the first fruits of the earth (Jas 1:18) will be harvested (Mt 24:36). We can rest assured that it will be as soon as the church is completed.