Seeds need warmth and water to germinate. Every seed contains an embryonic plant that sprouts and begins to grow when conditions are right. Until that time, the tiny plant inside the seed is protected by a hard seed coating. The seed coating begins to soften when exposed to the right combination of moisture and warmth and swells as water and oxygen are taken in, making conditions right for sprouting.
Each seed contains a food supply, or endosperm, that the seedling uses for nutrients until it grows to a sufficient size at which it can manufacture its own nutrients through the process of photosynthesis and by taking up nutrition from the soil through its roots. It is important at this time to ensure that the fledgling plant is given enough water to allow it go grow yet not so much that it deprives the seedling of necessary oxygen. Different types of seeds have varying germination needs. Some require bright sunlight in order to sprout, while others prefer to do so under the cover of darkness. Those who are attempting to grow their own garden flowers and vegetables from seed should adhere to the directions on the back of the seed packet for best results.