Most seeds do not need light to germinate. Since seeds often germinate underground and use the stored starch to germinate, light do not have a significant impact on them. But after germination, when the leaves grow, they need sunlight for photosynthesis to synthesize nutrients.
Three elements of plant germination: Wasser, air and a suitable temperature. Seeds will germinate when they detect the proper temperature and an adequate supply of water for growth. If not, they will remain dormant until the ideal environmental circumstances are met.
Sunlight is only required by some seeds, which are called “light seeds”, such as lettuce and carrots.
There are also seeds that do not need light and are better germinated in the dark, which are called “light-inhibited seeds”, such as green onion, leek and amaranth. But in general, light does not have much effect on the process of germination.
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