Say it is cloudy for weeks and barely any direct sunlight gets to your plants. How long could they survive under these conditions? And what could you do to help them out?
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They will survive just fine, they get enough light in the shade to continue growing. They just will not grow as gangbusters as they would if they were in a lot of direct sun.
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Another theoretical supplementary question then. Is there any difference in the quality of plants grown naturally outdoors and those forced with artificial light? If there is, which way round and is it significant?
sunlight has a broader spectrum and you have no choice at what intensity or what wavelength the plant is receiving so in that scenario your plant can turn out different than the plants grown artificially under bulbs with select intensities and wavelengths. Different wavelengths tend to different plant functions.
Yes there would be a difference in the plant characteristics and quality. Under artificial light you can select to strengthen certain plant functions under sunlight you can't. But in either case the plant would be healthy and can potentially produce bud.