Corking doesn't have anything to do with heat and sometimes mine get corking and sometimes they don't.

In fact there are some kinds of jalapeno's that won't cork at all, while some others cork easily! And like said above, it doesn't have anything to do with heat level

I live in a very hot and dry environment, I also allow my plants to almost dry before I water, I get lots of corking on my jals (2-varieties) and serranos, most other peppers are limited. I'm not sure if it is heat or draugt, I've heard both make a hotter pepper, so I'm happy to oblige them. Just my experience.
-Ethan

I thought corking actually made them hotter! Thank you for the insight. I guess I just don't have hot peppers this year! Thanks again.

Dave DeWitt's Fiery Foods

Here is a link that might be useful: Jalapeno info

Jalapeno M's are specifically designed not to be hot. "M" stands for mild. I'm growing Biker Billy's this year. They are supposed to be a larger, hotter Jalapeno hybrid from Burpees. They have corked, but even they are not firey hot.
John

Corked........

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