After your seeds have been planted, you need to cover them with more of the potting mix that you have dampened. Gently firm the potting mix on the top of the seeds. Read the instructions on your seed packet to determine just how much potting mix your should place over your seeds.
This will usually be worded as the depth your seed needs to be planted. As a general rule of thumb, the smaller the seed, the less coverage it will require. Some seeds, however, should barely be covered at all because they need the light to help them germinate.
Covering Your Seed With Potting Mix
Now that your seeds are properly in place in their pots, you should sprinkle some more water on top. This will help make sure the top layer of your mix does not become dried out. It also helps the potting mix firm up some more and makes sure it has proper contact with the seed.
Your pots should now be covered with some form of loose plastic.
You can do this by placing the entire container inside a plastic bag or to laying a sheet of plastic over your container or containers. This way, your seed will receive adequate heat and moisture. Another option is to purchase special trays that are made for starting seeds, which come with clear plastic covers. These containers can be purchased from most home improvement stores and garden centers.
Giving Your Seed Light, Heat, and Air
It is important to the success of your seeds for the container they are in to remain warm and free of drafts. Be sure to check your seeds daily, as most prefer a temperature anywhere from 65 to 70 degrees Fahrenheit. A good spot for storing your seeds in order to give them the proper temperature is on top of the refrigerator.
Unless otherwise directed, most seeds do not need light in order to emerge. Or, you can purchase a special seed germination heating mat from your garden center.
If you purchase a heating mat, be sure to place it below the pots your seeds are in because it should be heated from below. You will also most likely need to water your seeds more often if you use a heating mat because they tend to dry the potting mix out.
Regardless of how you decide to keep your seeds at the proper temperature, be sure to provide adequate air flow beneath the plastic. Otherwise, it can become too moist inside the container and mold may grow.
