it might surprise some folks, but most seeds don’t need light to germinate. now that you just read that i’m sure it seems obvious. seeds are planted in the soil, so they are in the dark, but from our early days of learning to plant seeds in little cups in grade school we put the cups on a windowsill so they would grow. it’s a tough habit to break. the reality is windowsills being next to windows tend to be pretty drafty and cold, not a great place to germinate seeds since the thing they really need is heat.
most seeds break they dormancy best when the temperature is between about 70 and 80 degrees – some need it colder some need it hotter, i’m making a generalization. with this knowledge we can grow better plants and save money. if you are growing plants using a light stand as described in the previous post or even in a greenhouse you can save yourself some money by delaying using them until the seedlings have sprouted.
t8 lights might be more energy efficient than t12 lights but they still use plenty of electricity and that costs money, each bulb pulling between 24-32 watts plus the ballast – equaling at least 60 watts per light.
since they don’t need lights, but do need heat you can save yr self some money by putting them under a heat mat until they germinate. the heat mat we use only pulls 17 watts, and running 24/7 that’s still much less wattage than the t8 lights running for 12 hours. you can also get much larger heat mats with controllers that fit many flats. we have one at work that fits as many as ten flats and it works very well. you usually you can find these from greenhouse suppliers. locally we go though bfg.
don’t want to buy a heat mat? want to save even more in electric use? next best choice is the back of the fridge, it puts off a good amount of heat. just resist the temptation to put them on the radiator – that will cook them. covering them with some plastic film will help keep the warmth in and humidity. happy growing.