Skotomorphogenesis is the development of a seedling in the dark, characterized by an elongated stem and an apical hook, while photomorphogenesis is the development in the presence of light, which involves a shorter stem and green, opened cotyledons. For cannabis seeds, both are critical stages: skotomorphogenesis occurs underground while the seed germinates, and the plant transitions to photomorphogenesis once the seedling emerges into light to begin photosynthesis. If ppfd not high enough skoto may not stop until she reaches light she needs.