Yes, it definitely makes sense to give the special seedlings special treatment! At least until you have an abundance of special seeds to work with, maybe next year. 
(Laugh.) “Frost” and “rain” are almost synonyms in my climate. Our last frost usually happens at the same time as our last rain, and our first frost usually happens at the same time as our first rain. 
Whereas here where I’m at, we had our “official” last frost date on the 15th, our actual last frost this year was the 6th, and we’re just about to head into our spring rain/storm season.
Nifty! Getting rain during the warm part of the year sounds quite nice. 
Maybe if we occasionally had clouds in summer (we pretty much . . . don’t have clouds), our heat and UV levels wouldn’t be so insane. 
My pepo squashes really do seem to love those 14 hour days of extremely hot, extremely high UV sunlight, though.