To start your own seeds, whether for a vegetable garden or a flower garden, the seeds need a soil temperature of 65 to 75 degrees F to germinate. Many home gardeners place their seed trays on top of a refrigerator or a hot water heater to achieve warm soil temperatures. However, if you don't have room on top of either of these appliances, you can use a standard heating pad, on low temperature, to warm the soil in your seed trays.
Put a layer of plastic wrap over the heating pad. Use the type that is microwaveable, as you know it will withstand heat.
Place the heating pad on a flat surface where you will be germinating your seeds.
Plug the heating pad directly into a wall outlet, and turn the setting to "low."
Lay a thin dish towel over the heating pad.
Set the seed trays on top of the heating pad and leave until the seeds have germinated.