ArtD said:Hi again Jeanne,
Although supplying bottom heat speeds up germination times, your seeds should germinate with or without it. BTW, most refrigerators today do not get warm on the top :-)
Your problem is going to be adequate light after germination. Sun from windows is not usually good enough. I hope your greenhouse has lighting or that you can get them hardened off and outside shortly after germination. If your seedling do not get enough light, they will become leggy and weak.
After germination, and until they go outside, cool temperature are best (65 degrees is ideal). Warm temperatures will cause them to grow faster and you won’t be able to supply enough light to keep up with the rapid growth.
Hope this helps a little,
Have to throw in my 2 cents' worth here...
First, I totally agree with the above, and with Art's other posts.
Second, I've been growing plants from seeds for a lot of years, and the worst luck I ever had with it was once when I decided to buy actual "seed starting mix" instead of using potting soil.
I have no idea why, but I had terrible germination that year!
Normally I use Miracle Grow potting soil... and yes, I know lots of people hate that stuff, but it's readily available here and I've always had good luck starting my seeds in it. I purposely buy the big bags that are "light" (and therefore, very dried out), because they're easier to haul around. Here's what I do:
Fill my flat of cell packs with the dry potting mix. Add seeds. Cover with more potting mix (except for extremely tiny seeds, which will just get pushed down into the mix a bit). Give the top of the flat a quick spray with the sprayer attachment on my kitchen sink on the lowest possible flow. Take one of the cell packs out and add water to the bottom of the tray to a depth of maybe 1/2 to 3/4 inch. Cover the flat with a plastic "humidity dome" (although in years past I simply covered with plastic wrap, which also works fine as long as you remove it as soon as the seeds start sprouting.) Put the flats in a warm place, say 70 to 75 degrees. Once the seeds start sprouting, put the flats under fluorescent lights -- I use plain old shop lights, so they need to be about an inch above the plants. When the potting mix looks (and feels) dry, I again take out a cell pack to pour water into the flat to a depth of about 1/2 inch.
That's pretty much it, until the seedlings are big enough to need to be potted up.
I think the moral of all of this is that we all find what works for us through trial and error! A big factor is whether you tend to over water or under water. I am in the latter group... very few plants have fallen victim to over watering under my watch (but more than a few have expired from extended periods of drought conditions
I hope you have great success with starting your plants, Jeanne!