When Was Tie Dye Introduced To Portland?

When I first arrived in the 1980s to Portland, Saturday Market and tie dye clothing were traditions already firmly established. Today that tradition is stronger than ever with several booths selling tie dyes in the current iteration of the COVID -restricted Saturday Market.

Popular culture would tell us that Ken Kesey brought tie dyes to Portland, and the nation, sometime in the 1960s.

This question is where the academics and serious amateurs are sorely needed.