I've grown cobaea every year. I start them off in individual pots and then transplant them and in my experience they don't require any special treatment. Mine germinate every year.
Last year they all failed miserably due to the lack of sun and all the excessive rain we had here in West Lancs so this year I'm giving them a miss.
I've just started some Canary creeper which aren't as fussy as the cobaea and I'm hoping for a better Summer this year along with everyone else.