You must have air present in the soil, light, porous soil not only contains air, but is a good growing medium for tiny roots. Now food is not needed for germination, the seeds can be sprouted on such mediums as moistened blotting paper or wet bricks as they contain enough food to grow until the first true leaves have been formed, after that they have to draw food from the soil, I always start my seeds in soil. To hasten germination some seeds will need special treatmnet such as Cannas, Moon flowers, Morning Glories and others with hard coats, they will just lie dormant a long time unless you soak these seeds overnight but placing in the soil to germinate. Some seeds of trees, shrubs and alpines require a treatment known as stratification by placing them in layers of sand covered with leaves, soil or straw. With Dogwood, the pulp is removed from the outer part of the seed and the seed is placed in damp peat moss in a refrigerator for four months before planting.
Many hardy annuals require long, cold, dark periods in which to germinate.
Now don't think that because I have told you about certain seeds that require more time, more work and certain conditions that the average flower or garden seed won't germinate in your light porous soil as it will and you have lots of seedlings for planting in your garden and in your flower beds. Inc. PageWise makes no representations about the content published on this site. PageWise hereby disclaims all warranties and conditions with regard to this information, and user agrees that all such use is at its own risk. If you are under 18, please do NOT opt-in to receive email offers on this page.