When I saw my first Herc I fell in love with them. Spent a lot of money lost a lot. If I did not love them so much i would have gave up on them about a couple hundreds of dollars ago. When they first came out I could not find any less than $20.00 a plant. I paid 15.00 for Palace Purple 15 yrs ago and it died the first winter.
What I have done to finally get to an acceptable survival rate.
-Grow them in pots. They just do not survive in my garden in the ground.
-Figured out they where not a dark shade plant. They need some sun and some wanted more sun.
-I have two that as long as I put a thick layer of rocks around the plant they do not heave in the winter. Greens Spice and Purple Palace......the only two I can grow directly in the garden and not in a pot.
Have you had to do anything different to grow them successful in your garden?
FYI
Pic of my first Herc I do not think the Purple Palace they sell these days even looks this good. Not a good pic because it was taken about 15-16 yrs ago.