*Ultra week 1 of the flower cycle is most effective applied on its own the last night of veg, preceded by 36 hours of darkness before switching lights to 12/12.
Amounts are mL per week, not per feeding, at pH 5.5–6.5. Foliars (Groigen & Florigen): 20 mL per 1 L of spray, covers 5–6 plants. Figures from Bloom Yellow Bottles feed schedules.