Marijuana light cycle for Vegetative growth
Sprouts, fresh clones and young plants live in what we refer to as the vegetative stage. This period has a long daytime and a short nighttime, like summer. It is during this vegetative stage that the plants send out much new growth. Large shade leaves form and act as sugar factories for the plant, turning sunlight into fiber for new growth. The plant needs to use as much food from the available light as it can, while it can.
This is why high nitrogen fertilizers are so beneficial during this period. The nitrogen, coupled with the extra light, acts as building blocks to the overall structure of the plant. As a general rule of thumb, in the indoor garden the average light cycle for the vegetative stage is 18 hours on and 6 hours off.
Marijuana light cycle shift for the Budding stage
At some point in the young plant’s development it becomes time to begin the shift to what is called the flowering, or bud, cycle. It is during this period that the plants declare their sex and produce large floral clusters that become the buds. This stage has a shorter daytime and an increased nighttime, such as late summer and fall.
The large shade leaves begin to die and fall off as the plant shifts its energy from producing leaves and stem to producing floral clusters. Food from light and nitrogen decreases, and the demand for phosphorous and potassium increases to fuel the process. During the early flower stage the plant will go through what appears to be a growth spurt as the stems stretch to catch the light that, if outdoors, would be coming at a lower angle as the season progressed.
The floral clusters sprout from the areas where the leaves attach to the stems, called “nodes.” The buds fill in the nodes and progress out. And, as we all know, it is strictly the female plants that develop into our high quality and most desired sensimilla. Indoors, the typical light cycle used in the bud stage is 12 hours on and 12 hours off.