(3) Sunlight Explanation: Plants need sunlight to conduct the carbohydrate-making process called photosynthesis in their green leaves and stems. Seeds do not contain green pigment, but merely a dormant embryo. Seeds do not need to bask in sunlight to germinate. However, the warmth frorri sunlight can create a soil environment more, conducive for gemination. The requirements for seed germination vary among all plant species.