Return to the Growing from Seed Forum | Post a Follow-Up

1st time heat mat set-up...advice?

Posted by bosewichte 5 (My Page) on
Fri, Mar 9, 12 at 11:30

For too many years I've tried to start seeds indoors (germinating on hot water bottles, in sunny windows, etc.) only to have leggy, weak seedlings that don't make it in my garden.

This year, I'm getting serious. I'm getting ready to purchase a Hydrofarm Seedling Heat Mat (48 x 20"). I just wanted to make sure I'm doing this right...the heat mat will be set up on top of an insulating piece of foam core in my cold basement. It's usually 50 - 60 degrees down there. I'm planning to go to Home Depot and buy a fluorescent light. So, leave mat on until seedlings pop up, uncover them, and put the fluorescent light a few inches over the seedlings, raising the light as the seedlings grow. Keep them moist.

Is that all there is to it? Will the heat mat be enough to germinate the seeds in my cold basement? I should say that I'm only growing flowers, no veggies. Will an ordinary fluorescent light provide enough heat, or should I get something else? Is 2 - 3 inches above seedlings enough distance?

Thanks so much for your help! I hate to put out all the money to buy the mat, seeds, and light if it's not going to work. Oh, by the way, do I need a thermometer? I don't think my mat comes with one.

Also...any guess as to how many seeds I can fit on a 48 x 20" mat?

Thanks again!

Follow-Up Postings:

RE: 1st time heat mat set-up...advice?

the heat mat will be set up on top of an insulating piece of foam core in my cold basement. It's usually 50 - 60 degrees down there

Then the heat mat is going to be trying to heat your whole basement and will quickly burn out. It is triggered by ambient temperature.

Even if you buy the thermostat control for the mat it still need to be in a confined enclosure of some sort, insulated from the rest of the basement.

Check some of the other posts here about using heat mats to see what others have used to create a temporary enclosure to contain the heat. Even a large box or a small tent made from plastic can make a big difference.


RE: 1st time heat mat set-up...advice?

Thank you...I will do that!

building a seed starter outside

i want to build a frame to start seed outside. I plan to erect a small structure that will heat easily and equal across the growth platform.Using what ever is handy (I am retired and on limited income).The structure will be 8 foot long and 3 foot high and 3 foot wide the out sides will be used sheet iron covered inside with batted insulation the "heat tunnel" will be some sheet insulation I was given. I will have a flat piece of material covering the three segments with an entrance at the far end from heat source blowing down the "heat tunnel" exiting and returning up a 2 inch space between first material and black painted sheet iron.The top will have raised edges and lined with a plastic material covered with old blankets burlap or other to hold water I will have stiff wire bowed to cover all with adjustable heights to limit space above seed pots to aid in heating the soil. I will cover them with black material until seed sprouted.This structure will be placed in an open area with wind protection and plenty of sun am I wasting my time? Please e mail me at with your comments btw the heat process will be much like a meat smoker where heat will be channeled to far end and then bought back to heat source via another small channel and plants will be watered by capillary action from the bottom of the top pan. Only a test run this year to see if applicable

RE: 1st time heat mat set-up...advice?

You say you are GOING to buy a fluorescent light? I'm assuming you didn't have one before. That and that alone will give you leggy spindly weak seedlings.
Between the heat mat and the lights you will see a world of difference. Good luck and happy growing!

RE: 1st time heat mat set-up...advice?

Oh, definitely, we're getting a fluorescent light! Fingers crossed that everything will work!

 o Post a Follow-Up

Please Note: Only registered members are able to post messages to this forum.

    If you are a member, please log in.

    If you aren't yet a member, join now!

Return to the Growing from Seed Forum

Information about Posting

  • You must be logged in to post a message. Once you are logged in, a posting window will appear at the bottom of the messages. If you are not a member, please register for an account.
  • Posting is a two-step process. Once you have composed your message, you will be taken to the preview page. You will then have a chance to review your post, make changes and upload photos.
  • After posting your message, you may need to refresh the forum page in order to see it.
  • Before posting copyrighted material, please read about Copyright and Fair Use.
  • We have a strict no-advertising policy!
  • If you would like to practice posting or uploading photos, please visit our Test forum.
  • If you need assistance, please Contact Us and we will be happy to help.

Learn more about in-text links on this page here