Indoor cannabis cultivation refers to intentionally growing cannabis plants inside a sealed structure or private residence using artificial lighting instead of sunlight. Precisely controlling the daily and seasonal light cycles indoor growers expose plants to makes it possible to intentionally induce and sustain flowering year-round independent of outdoor climate and seasons. However, building out a dedicated indoor grow space requires substantial initial investment in grow lights, ventilation systems, air conditioning, dehumidifiers, irrigation and other equipment necessary to manually recreate ideal conditions. While more expensive to operate than outdoor cultivation, the ability to grow cannabis indoors year-round allows more frequent harvests and higher plant yields overall. Although startup costs are steep, advanced indoor growing tactics also allow cultivators to fully control all environmental inputs and plant nutrients in order to optimize conditions and bring out each strain's maximum potential. Ultimately, closet and warehouse-grown indoor buds reach heights of potency and quality largely unattainable with outdoor growing relying solely on the power of the sun - albeit completely free of charge. There are compelling pros, cons, and unique challenges to both approaches.