This is one Ping I can not keep alive at all. I tried 3 times growing P. primuliflora.
One in equal parts perlite, peat moss, and LFS.
One in the same mix but I read where it likes it very wet, so I kept the water just under the soil.
One in live LFS and I could not grow any of them, for the most part.
I can grow them usually over the summer, but when fall comes the plant dies. Actually rots, even if I keep the soil almost dry.
The Mexican Pings are so much easier to grow. I have not had any problem with any of these.