First time I've grown padron peppers. I'm gonna play around with them this weekend. 

Please forgive typos in previous post. Pollen count is high and my eyes are watering like little creeks.

I hope you don't think I'm rude, but you really REALLY don't want your padrón peppers to turn red. They are best picked small (a couple of inches long—the thickness of your thumb—and green). There is a rumor—which I've found to be false—that one in ten is profoundly hot and spicy. I've eaten hundreds, if not thousands. The larger they are, the hotter they are, and once they red, they can be perishingly spicy.

The true padrón flavor, as achieved in Spain, is easy to produce. My method is a bit of a cheat, but ti's fun. I use a large cast iron skillet with a coating of good olive oil. Shake the peppers in the hot pan until they're coated with oil, and give them a dusting of flake salt. The peppers will start to brown—here I cheat with a blowtorch, to get into the crevices and speed things along. They will blister, puff, darken, and wilt. I pop them out onto newspaper to remove most of the oil, and serve them while still warm.

You might kill your guests with red padróns, unless they are fans of peppers hotter than habaneros.

Read about the chef and farmer who brought the craze to San Francisco, where the padróns are sold by the tonful at the farmers markets. (We have eight plants, courtesy of lovely Cynthia Sandberg at Love Apple Farm—she brings them to my for birthday every year!) This is written by Andy Griffin, the John Steinbeck of farmers.

http://newfarm.rodaleinstitute.org/columns/CSA_journal/2004/0904/padron.shtml

Rick Bayless Hello! What is the heat profile of these Padron peppers? I have read that the Spanish Padrons vary widely in heat. In your experience, when you have grown in Chicago, have you noticed a lack of heat relative to the type of chili? Do you know of any varieties of chile that retains heat regardless of growing zone? Or are all chilies grown in lower sun climates doomed to blandness?
I am a gringo living in Norway...a bit farther north of the Windy City.