Jack Herer

Environment

Tends to prefer a warm, well-ventilated environment — daytime temps in the mid-to-upper 70s°F (roughly 24–27°C) with a modest drop at night. Keep relative humidity in the 50–60% range during veg, stepping down toward 40–50% in flower to protect the developing buds. Good horizontal airflow across the canopy is important given the bushy, branchy structure this lineage tends to build. VPD should be kept in a moderate range; this type generally dislikes stagnant, overly humid conditions.

Training & canopy

Well-suited to topping early in veg to control apical dominance and encourage lateral branching — this lineage often throws aggressive main-cola stretch if left untrained. LST works well to open up the interior canopy and is a natural complement to topping. A SCROG net is a strong option once multiple tops are established, as it helps manage the stretch and distribute light more evenly across what can become a wide, unruly canopy. Avoid heavy defoliation; the open, branchy structure often handles light naturally.

Flowering

Flowering window is unconfirmed for this specific cut, but the sativa-dominant lineage (Skydog, NYC Diesel, Headband) suggests a flower period likely in the range of 9–11 weeks from flip. Expect a pronounced stretch in weeks 1–3 of flower — potentially doubling in height — so flip to 12/12 while plants are well below your target canopy height. Bud development tends to be gradual, with significant calyx stacking happening later in the cycle (weeks 6–9). Watch pistils and trichomes rather than relying on a fixed week count, as pheno variation in this lineage can be meaningful. A longer, patient finish is usually rewarded.

Difficulty

Sativa-dominant hybrid lineage means notable stretch and a longer flowering window that rewards growers with some canopy management experience.