marijuana horticulture book

Male Pre-flowering

Marijuana Horticulture

by Jorge Cervantes

Male pre-flowers are normally visible when plants are six to eight weeks old, after the fourth week of vegetative growth. The pre-flowers emerge behind the stipule at the fourth to fifth branch internodes and generally do not turn into full flowers.

Always wait to induce flowering until after pre-flowers appear. Inducing flowering iwth 12 hours of uninterrupted darkness and 12 hours of light before pre-flowers develop will stress the plant. This stress could cause peculiar growth, and plants might develop into hermaphrodites. Inducing flowering before pre-flowers form will not expedite flowering. In fact, flowering will occur at about the same time as if yu had waited for pre-flowers to show!

Plants grown from seed under a 24/0 photoperiod will generally show pre-flowers after plants that are given a 18/6 day/night photoperiod. Once pre-flowers are distinguishable as male or female, plants can be induced to flower with a 12/12 day/night photoperiod.

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