Gypsum for gritty mix
I posted a note in the adenium forum, but perhaps this is a better place for this question.
I finally obtained all the necessary ingredients for the gritty mix - all except gypsum. I went to four different garden centres yesterday, and couldn't find it anywhere, nor could they tell me where to find it. I also called a few of the big box stores, with no luck.
Does anyone know where I can find some in Toronto, Canada? Alternatively, is there anything else I can use as a suitable substitute? I've also been unable to find Foliage Pro in Canada, so switching to that fertilizer does not appear to be an option.
Thanks in advance!