Many plant species can technically grow to a degree without light but they cannot develop, perform or reproduce as naturally intended. Seeds can germinate without light and small roots and seedling plants can grow but they will be weak and likely not be viable unless placed into a lighted setting. Light is required by all plants to conduct photosynthesis to make use of and develop nutrients and without it they cannot survive to reach a full lifespan.
Light Spectrum Requirements
Plants thrive under the bright full spectrum light, which natural sunlight provides. When plants are grown indoors, this natural full spectrum sunlight can be supplanted with application of artificial light from all manner of high performing light bulbs. Most important for plant growth and performance are the red and blue hues in the visible light spectrum.
Daily Light Exposure
Most plants require upward of six hours of bright sunlight or artificial light in the proper spectrum hues every day. Some plants will require or thrive with much longer light periods up to 14 hours per day. Most plants also require a night interval or no light rest period for optimal growth and performance.