I stratify seeds for only a few weeks. Keep in mind that many penstemons aren't hardy up here. Give it a try. Plant them in cell paks and put in the fridge.

You could also do it in early spring which would give them time to grow more and adjust before winter. I cover mine with loose leaves before winter.

That is a great idea to put the seed trays right in the refrigerator. (That gives a whole new meaning to refrigerator science experiments...) I now have them in self-watering 24-cell seed trays, with additional lower trays filled with water and a cloth that wicks the water up into the germinating mix. Should I put the whole kit 'n' kaboodle, including the water-filled lower tray, into the refrigerator, maybe all covered with a plastic bag?

Of the two species I want to grow from seed, the chart I have lists Penstemon palmeri as hardy in zones 4-9, and P. eatonii zones 3-8. I'm in 6b. But you might not be referring to our cold winters, but rather to our summers that come with a lot more rain and atmospheric humidity than in these plants' native regions. I know that can be a problem. Both Penstemons I planted last year (P. barbatus 'Prairie Dusk' and P. stricta) did make it through the winter fine and it was a joy to see them.

I love them, too, and so do the hummingbirds.

I put them in a plastic baggie in the fridge. Mostly, though, I start seeds in March and stratify them on a cold windowsill before putting them under lights. That works for me.

You don't need the water trays in the fridge.

Thanks. Into the refrigerator just went two 24-cell seed trays (each about 15" x 9") filled with germinating mix and Penstemon seeds, covered by their plastic dome. I guess they'll keep the tabouli company on the shelf above.

When I'm in my right mind, I start seeds in March. Over the last few weeks, though, I've been gripped by the thought: I can go to a nursery in September and get perennial plants for planting; fall is the time for most root growth and September a perfect time for planting. Why can't I grow my own plants over the summer? I'll probably do the whole process indoors under grow lights, since it would be hard to keep seeds and young seedlings adequately watered outside in the summer.