There are many different kinds of seeds. Some plants make a lot of seeds, some make only a few. Seeds are often hard and very small, but some are larger. The coconut is as big as a child's head, but it contains more than just a seed. At the start, seeds are "dormant" (resting inside their coat) for a while. When the seed is ready to develop, it needs water, air and warmth "but not sunlight" to become a seedling.