Thanks everyone, I am going to read through EVERYTHING!!

Trouble is, you get a spare couple of hours, post all your forum and facebook questions, then sometimes get a surprising response!! Then you have to wait till your next couple of hours of clear-head time

Oh boy Ralph, you are much braver than me! I grow my South American cacti in a mix of lime-free sand, lime-free clay, and pumice gravel! I admit I've added a bit of oak leafmould to this mix for Cleistocactus. But I fear the organic component! I'd say it was you who is brave! Sand, and even more so...

Oh boy Eltel and Terry, It would be so much easier if the manufacturers just stated on the box, and online, what they actually have in their fertilisers. No! it would make you worried .... because the paper list of ingredients would be bigger than the feed cannister! And in nature the plants just t...

I use a general purpose house plant fertilizer and never worry about alkalinity, trace elements and so on and my cacti are doing just fine. I was a bit hesitant to bring it into the mix :grin: , but somewhere along the line I also read that it's possible we haven't been giving out C&Ss enough n...

Oh boy Eltel and Terry,
It would be so much easier if the manufacturers just stated on the box, and online, what they actually have in their fertilisers.

Well, I grow my South American cacti in Ericaceous compost (for lime hating plants) with added coir and granite, and they are doing very well in it. I do add crushed shells as a top dressing for a few lime loving other plants, however. Plants are fed with Ericaceous Miracle Grow. Oh boy Ralph, you ...

Sorry, but a bit of chemistry is needed. Sulphur does not normally exist as an anion S(2-) although dissolving hydrogen sulphide in water does generate the smelly hydrosuphide ion HS(-) of no interest to horticulturalists. The anions that we are interested in are composed of sulphur and oxygen of w...

I once found this on the WWW. I hope it helps. https://www.rrm.me.uk/Cacti/Cactus%20and%20Alkalinity.pdf Thanks Kees, that is a very interesting article! I haven't read it all, it's pretty sizeable! But it seems to be more focused on the issue of alkalinity in association with calcium, rather than ...

Karsty ... don't wish to be pedantic .... but .... which one? There are many ... and will have so different effects on the plants. I'm no horticulture expert but would say a quality growing medium and a quality cactus feed in the stipulated dilution would be more than adequate. Hi eltel, No that's ...

Gerald - I don't use tap water on any of my plants. I only use rainwater collected in water butts from roof run-off. There is a very clever chap who grows orchids on YouTube who has a a history in hydroponics, who says that calcium in the form of carbonate is difficult for plants to absorb anyway.....