Filled the jars with potting soil and seeds - and placed them on the window sill and watered them almost-daily:
I started out watering them daily, but sine there's nowhere for the water to drain out of the jar, I started waiting until all that water had soaked in before watering them again. Perhaps that was my mistake. Or maybe this spot doesn't get as much sun as I thought - or at least, doesn't get enough sun to start the herbs from seeds? Who knows.
It's been 9 weeks, and all I got were a couple oregano sprouts and 1 long cilantro sprig - but neither continued to grow or thrive. RIP herbs.
It's a fail. But I tried! :)