Q.What Winter Conditions Will Jacob’s Ladder Tolerate?
I live at 6, 000 ft in southern California, have lots of shade in my garden, but my soil is mostly decomposing granite.

This article should help: https://www.gardeningknowhow.com/ornamental/flowers/jacobs-ladder/growing-jacobs-ladder-plant.htm
Polemonium is hardy zones 3-9 depending on the cultivar.
Jacobs Ladder grows best in full to partial shade areas in well-drained, evenly moist soil. The soil should be rich in organic matter, with a soil pH of 6.1 to 7.8. Too much sun or heat should be avoided because the leaves are prone to scorching.