Problems with germination for surface-sowed seeds
I just cant seem to get any of them to sprout. I'm trying to grow seeds that 'everyone' says are really easy to grow, but from several attempts now, I have had zero success.
These are the seeds I'm trying to grow: Allyssum, Violas, Trailing Lobelia, and (soon) Hardy Begonia.
My technique is probably to blame, although I have a feeling I need to be doing something extra for these seeds. For instance, I followed the directions for cold stratification for the violas, but still no luck after a couple of weeks.
This is how I've sowed them so far -- I prepare a seed starting mix with half soil-less mix and half perlite. I moisten the soil, then I scatter the seeds on top. (I do not 'press into surface' because the seeds always stick to my fingers). I spritz them with a water mister, then I let sit in a bright room (no direct sunlight). I've tried varying some things in hopes that I might get them to finally sprout, I've put plastic baggies now over the pots so keep things humid. I've tried putting my allyssum outside, thinking that it needed 'cooler temps' to be happy. I'd really prefer to direct sow some of these guys since they probably don't like to be transplanted, but if I can't get them to germinate in a controlled, moist environment, then how am I going to get any plants outside?
Things that I know that I'm doing right: sterile potting medium, keeping the soil evenly damp but not soggy, and not putting them in direct light where they'll burn.
What am I doing wrong? Am I overlooking some other variables? This is surprisingly difficult for me, and I could really use some advice. What's the big secret for successful surface-sow germination? (Is there any?