Shoutout to the retired guy in Flagstaff who let me poke around his 1970s raised beds
His beds were cedar 2x12s from a yard sale, still solid after 40 years with nothing but linseed oil, and now I'm staring at my own pressure treated pine build from 3 summers ago wondering if I picked the wrong wood, so what are you all actually building raised beds out of these days?
Linseed oil is good stuff but cedar in Flagstaff lasts partly because of that dry air, not just the wood. Wet climates will eat cedar a lot faster without some kind of finish touch up every few years. My uncle's cedar beds down in Oregon rotted through in about 12 years, so climate does a lot of the work.