After two years of trying, I finally have my first delphinium germination!
They are supposedly one of the harder plants to start from seed, as the thick seed casings require several freeze/thaw cycles to crack open. These I had left in the fridge for months and then given a 24 hour soak before sowing; I had tried before to do a week or two in the fridge and the soak with no luck, so I don’t know if I was literally lucky to get one to crack or if the extended period of cold was necessary to trick it into thinking it had been winter, but I’ll take it.
Given my past troubles, I also tried two trays of “winter sown” seeds that are currently still outside with no signs of life yet. A large number of the seeds I had collected last year ended up in those, so I’m hoping those will still be fruitful as it warms up.
I still consider this a big win!