I have just bought a "Kleims Hardy" gardenia and given our wet and sometimes chilly weather here in British Columbia I think it is best in a large pot. I have no idea what soil to use in the pot! I read on another forum a sticky about a soil for container growing but am not sure if that is right for this plant. Suggestions, anyone? Thanks.
Gardenia planting medium
Mine grows in the ground, in sand/leaf litter, so maybe some potting soil, mixing in equal parts of sand and compost.
I have my Kleims growing in plain old Miracle Gro potting soil. They are now getting buds, so they must be happy. Good luck. I lost my old Kleims just last year. Have no idea what happened to make it die. All of mine are in pots.
And as we all know I tend to kill the ones in pots (ok...once brought indoors at least). The mix I like is any or all of the following: Expert soil (or whatever you have up there with a "fluffy" feel), perlite or rice hulls, vermiculite (when I have it), and bird grit (sm amt) - then of course I add worm castings, extend release fertilizer (dynamite) and Holly Tone.