Thanks Pat, Cindy and Arlene! Epsom salts sounds easy and natural, and sounds like I could just use it in addition to my osmocote. And, your slow-to-increase cultivars sound right up my alley - I'll gladly try some dormants here, though they usually want a much colder winter, in order to bring some of those genes into my hobby pollen dabbing pool (and very pretty ones, at that!).
Seed, some of my more vigorous growers are or have included:
Baby Betsy (!)
Bobbie Gerold
Cosmopolitan
Dixie Land Band (!)
Double Overtime
Frankly Scarlet (!!)
Highland Lord
Hush Little Baby
Janice Brown
Jungle Princess (!)
Ladybug's Two Moons
Lullabye Baby
MacMillan Memorial
Mardi Gras Parade
Nagasaki
Pink Flirt
Prairie Blue Eyes (!!!)
Purple de Oro (!!!!!)
Rose Emily
Seductor
Siloam Olin Frasier
Sings the Blues (!!!!)
Super Purple (!)
Trahlyta (!!!)
Tropical Centerpiece
Uninhibited
Vintage Bordeaux
Woodside Ruby
As always, your mileage may vary on how quickly any might increase, but I've added (!) to those that are really quick ones here (I'd be tempted to declare Purple de Oro an invasive weed if it weren't a nice daylily for people who want fast increase). And, not all perform well in other ways (color, size, health, etc.) Most just have steady-but-Too-Quick-for-me increase here, meaning they consistently double or better yearly, and I'm looking for none-to-little increase in mostly evergreen/semis (zone 9b) so that I can enjoy a lot of various cultivars while avoiding the need to dig and divide a lot. And, I'll be trying out a few more dormants if that's where the slower increase genes are clustered!