I started tomatoes on 1-25 one time. I had a small home made greenhouse that was attached to the house. I told myself that I would never do it again. The tomatoes did very well but it was too much work lifting them through the window in and out of the house (I had no heat in the greenhouse). I had to pot up to many times, using too much potting soil and too many pots. Of course I gave plants to many people, plus I planted too many plants. The project was too much work and cost too much to try again.

Larry

Those little radiators will radiate heat outward, but they usually don't have fan blowers, so the heat is slow to disperse into a wider area. You may need to set a fan in a spot where it will blow the heat from the radiators over a wider area so that a bigger area is heated and not just the few square feet closest to the heater.

Do you intend to let the seeds germinate on the enclosed porch in flats that are sitting somewhere near the heaters? With space heaters, there's always a risk of fire if any combustible materials are placed within 3' of a space heater, so I hope you're not intending to set the flats directly on top of the heaters.

I don't know what sort of seeds you're starting, but if you're talking about warm season seeds, I agree with Larry that it seems too early to me. I haven't started seeds of anything yet and I'm more than 100 miles south of you, where (presumably) we warm up earlier than y'all do.

Can you sprout the seeds someplace indoors and then move them out onto the enclosed porch after they sprout? Lots of people sow the seeds in a flat and set it on top of an upright freezer or refrigerator to sprout. It usually is warm enough on top of those appliances that the seeds will sprout quickly.

Also, if I was going to move young seedlings to an enclosed porch to grow after they sprout (and I've done that lots of times), I'd buy a Min-Max thermometer (Wal-Mart and other big box stores have them for a really good price) and put it on the porch for a few days and see how hot the porch gets during the day and how cold it gets at night before I put any seedlings out there. Enclosed porches (particularly if they are enclosed by walls of windows) without an HVAC system can get really hot on sunny afternoons. Your porch should stay warm enough at night for the seedlings once they've already sprouted, but the only way you'll know for sure that the porch is staying warm enough is if you have a Min-Max thermometer out there on the enclosed porch.

Different plants have different temperature needs as they sprout and as they grow on. Some do well in cooler temperatures while others stall and barely grow at all if they are staying too cold, so much depends on exactly what it is you're germinating/growing.

Like Larry and Dawn, I won't start anything this early. In midFeb I will start my seeds with bottom heat in a planting bench that I can close off at night. I have in the past started a few tomatoes and peppers indoors on top of a regular heating pad, set on low and covered with a folded towel. That might be an option for just a few seeds. Then after they are up you could move them out to your porch.

thank you all for the input actually i have this love affair going with greens....i want to start some kale and chard right now nothing warm weather.....

Ah, unless you don't have space, you need a cold frame! I'm still learning to use mine. :\