Get some heat tape (flex-watt) about 2.50 -3.00 per foot or a reptile heat pad from a pet store. They go for about 1/3 the price garden shops charge.

Get some heat tape (flex-watt) about 2.50 -3.00 per foot or a reptile heat pad from a pet store. They go for about 1/3 the price garden shops charge.

Get some heat tape (flex-watt) about 2.50 -3.00 per foot or a reptile heat pad from a pet store. They go for about 1/3 the price garden shops charge.

An incandescent bulb in a box is a cheap low-power heat source, but they don't come with a built-in thermostat. You can use the long thin types under a long shelf. A metal shelf will spread the heat pretty well, but you might want to fix a thin sheet of metal to a wood shelf or you'll get a hot stripe with cold edges.

Alternatively, use the lights above the plants to heat them. Enough light for most seedlings is usually enough heat that you need a fan to keep them cool.

I have my television close to a window and I put my pots that need light on top of the TV with a plastic sack over the top. If the seeds don't need light to germanate I put the flat(old cake pan) with containers(old cool whip ect.) a plastic sack over all and put on top of my refrigerator towards the back where the heat comes up. I've started seeds for years this way.

I use two methods for growing alot of seeds. I have a sone ledge in my living room which runs the length of the room. The baseboard heat runs along side of it. I place the trays on the ledge and have the best sucess. The stone holds the heat. When I run out of room I put other trays right above my light fixtures.I get the lights as close to the bottom as possible. The heat from the light hoods warm the bottom of the trays. When germinated I move the lights above the trays. The heat from the light fixtures work. I don't use lights to germinate. Jane

I made a box out of 1 by 6" boards and plywood. I installed two incandescent light sockets, and wired them in series (not parallel). I use ordinary 60 watt bulbs. Because of the series wiring, each light only gets half the voltage. The result is lower power consumption, and more even heat than if I had only used only one bulb.

Some sort of heat deflector would help to even out the heat, but I haven't done that yet.

I made the box 4 feet long so that the shop-light (pvc fixture), would fit on top of it. It's a nice, compact setup.

John

water bed heaters (12"x36" mat typically) work well, have thermostat.
Pick them up at Goodwill, salvation army or local thrift store.

For anyone interested in putting together a home-made bottom heating fixture, I have a suggestion. Digikey sells bi-metal thermal switches. These are used in devices such as hair-dryers and portable electric heaters to prevent over-heating. They are not adjustable, but are available at various temperature ratings. When that temperature is reached, the switch opens. I'm going to use one to switch on/off two incandescent light bulbs in a bottom-heating fixture I built.

Try this website: www.digikey.com
Search for Bi-metal cutouts or thermal switch.
The device is manufactured by Cantherm.

John

I put the flats under the florescent lights. A couple inches off the flat warms them nicely. Most seeds come up within 10 days. Water the flats every 2-3 days, tends to dry out quicker under the lights.
Dave