I thought the white deposit (sometimes fluffy) came from lime salts in tap water. I used to get this deposit on clay pots when I used tap water years ago but since using rainwater (from the wild hills of Wales) I've seen no trace whatsoever.

...but I think many of us simply don't give our cacti enough water for there to be any seepage from the bottom of the pots, so there're no issue there at all. With most of my cacti, I water generously and ensure that water comes out of the bottom of the pot (into a bucket). This has the double effe...

DaveW wrote:There are only a few occasions now when compost retention is a problem.

I find that even with small multi-holes in plastic pots, the soil tends to dribble out over time, which is why I put a single thickness of kitchen towel in the base of all my pots.

Yes, these articles turn conventional thinking on its head. I've seen similar research results before. The traditional "crocks at the bottom" theory seems logical but it is clearly wrong. I stopped putting coarse material at the bottom of my pots some time ago. All I use now is a piece of ...

I always water my cacti & succulents with water collected from the greenhouse roof into four water butts. I periodically test with litmus paper. It always reads at around 5.5, which is just about right.

Let's not create a separate forum. I'm a lumper!

Just had a quick flip through the above site for Lobivia , and unfortunatly a fair proportion are either wrongly identified , or hybrids : not much use unless you already know the id of the plant in front of you ! I also had a quick look on the a/m site at Ferocactus and Lithops. As with lobman's e...

DaveW wrote:How quickly we forget last year:-

http://www.dailymail.co.uk/news/article ... itain.html

To quote an old song - "Oh yes, I remember it well".

Christer Johansson wrote:...but that will be in another report later

I can't wait!

I thought it was just watered down meths. I'd be surprised if isopropanol harmed plants more than ethanol/methanol - any evidence for this? Methylated spirits is different chemically from Isopropyl Alcohol. I'll try meths next time I see a mealy bug on cacti/succulents to see whether it is as effec...