Normally, the heat mat and cover should be removed after the seeds have germinated, even if the sprouts are small. In fact, some folks never use the cover at all. If a person can make sure the soil doesnâÂÂt dry out, itâÂÂs probably actually best not to use a cover.

If the air temperature gets down to 60 degrees at night, the soil temperature will be lower than that. However, I donâÂÂt think that would be a problem at all. Are you figuring on leaving the plants on the windowsill, with no other source of light? I doubt theyâÂÂll really get enough light that way. If you could move them off of the windowsill and under a fluorescent light set-up of some kind they would be much better off.

Art

Thanks Art, I will work on getting a light system!

You can get two T8 bulbs and a standalone fixture at lowes/home depot for about 30 dollars total. I've got mine set up infront of a window and the fixture as well on a timer, so its only on during the day so my neighbors don't get mad at me lol. I hope its enough light for them to thrive. (Note the seedlings should be much closure to the light, within an inch or two. The bulbs don't get hot)

ThereâÂÂs an interesting older post (see link below) about heat mats. Probably should have included that in my first post.

Art

Here is a link that might be useful: Heat Mats

Thanks Art and Syntria for the great responses!