Germination is a process where plants and other organisms emerge from gymnosperm/angiosperm seeds and start their growth. Gymnosperms are seeds that are not protected by an ovule. Angiosperms are vascular plants that grow fruit and flowers, which are protected by ovule. Sprouting of a seedling from a seed is an example of germination. Fully developed seeds contain an embryo, that store food reserves and are wrapped in the seed coat. Some factors of successful germination include water, oxygen, temperature, type of soil, and light intake.
The key factor in determining the habitable zone of a planet is looking for a Earth-like planet that is able to have water on it's surface, and make sure that it can still give or support life.