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Vegetative Stage
Definition: The vegetative stage is the growth phase between the seedling stage and flowering, when a cannabis plant builds the leaves, branches and roots that will support its buds. Photoperiod plants stay in veg as long as they get about 18 hours of light per day, while autoflowers usually veg for only 3 to 4 weeks.
How Vegetative Stage works
Veg is the construction phase. Every branch you grow now is a potential bud site later, so the size and shape of the plant at the end of veg largely sets your yield. Vigorous plants can add 1 to 2 inches of height a day at their peak.
Veg conditions
- Light: 18/6 is standard for photoperiods, at 400 to 600 PPFD.
- Temperature: 70 to 85°F (21 to 29°C) with lights on.
- Humidity: 50 to 70%, or a VPD of about 0.8 to 1.2 kPa.
- Nutrients: nitrogen-forward feeding, increasing as the plant grows.
How long to veg
Indoors, 4 to 6 weeks from sprout is common, but the right length depends on your space. Plants typically grow 50 to 100 percent taller after the switch to flower, so many growers flip when plants reach about half the final height their tent allows. Outdoors, photoperiods stay in veg until late-summer days shorten.
Training window
Veg is the time to shape plants. Topping, low-stress training and transplanting all go best here, while the plant can recover quickly. Finish heavy training at least a week before the flip, and move plants into their final containers 1 to 2 weeks before flowering so roots are established when buds start forming.