Xmas Light Seedling Heat Mat

the999bbq · January 22, 2009

I like it how this discussion is still in motion ;-)
I am sure you have better germination with the underheat, you just mimic a heated soil, what most heat loving crops love more than just 15°C ambient room temperature. In the propagator you not only have the underheat but a relatively higher moisture too so all helping the germination. For fresh seeds the difference will probably be not that big, but maybe tricky seeds (older,...) could use that little extra TLC.

About the uneven heating, that's most likely related to the way the coil is guided in the device. I think I have lowered the uneveness by adding about an inch of moist soil in the propagator, levels the bottom, serves as a heat buffer (the propagator is more off than on), and spreads the heat a little bit more than the 'naked' bottom would do. The thing with tools is that you should use the right tool for the right job, heating with lamps is possible but you waste most of the energy for something that some already consider to be a wasteful activity.

My thermo is set to 20°, and maybe a bit higher for the peppers, germination is as little as a few days, usually less than a week.

with the warmth under their feet the seedlings grow very fast so in my setup the ones that are up are removed from the propagator.

January 22, 2009	#18
the999bbq Tomatovillian™ Join Date: May 2007 Location: Belgium Posts: 191	I like it how this discussion is still in motion ;-) I am sure you have better germination with the underheat, you just mimic a heated soil, what most heat loving crops love more than just 15°C ambient room temperature. In the propagator you not only have the underheat but a relatively higher moisture too so all helping the germination. For fresh seeds the difference will probably be not that big, but maybe tricky seeds (older,...) could use that little extra TLC. About the uneven heating, that's most likely related to the way the coil is guided in the device. I think I have lowered the uneveness by adding about an inch of moist soil in the propagator, levels the bottom, serves as a heat buffer (the propagator is more off than on), and spreads the heat a little bit more than the 'naked' bottom would do. The thing with tools is that you should use the right tool for the right job, heating with lamps is possible but you waste most of the energy for something that some already consider to be a wasteful activity. My thermo is set to 20°, and maybe a bit higher for the peppers, germination is as little as a few days, usually less than a week. with the warmth under their feet the seedlings grow very fast so in my setup the ones that are up are removed from the propagator.