Soil questions

[Auxnorm]

I have used this http://www.debco.com.au/products/potting/cacti.php I have used it in the past and seems to drain well and cactus that have been in it for years have seemed happy enough.

In my identification post a comment on how the soil looks extremely rich and almost mud-like has me wondering if I bought I mix that's less than optimal.

This picture, no it's not sick from being in this soil I only just re-potted it and hoping it will pull through. The mix was moist when used, when should I water re-potted cactus? A have read a few different ideas. Sometimes I leave them and others I have watered after re-potting



EDIT: Great I just read about this mix here http://www.australianethnobotany.com/vi ... f=7&t=4029 and I did notice some wood chips and come to think of it the old mix from the pots looked nothing like this mix I thought it was just that it was old though I think it was more sandy. I thought I used it before now though I hope it will be ok I re-potted everything in it....

[daiv]

It should be illegal for them to sell a bag of wood ships with a label that claims to be suitable for "all varieties of cacti and succulents".

Here in the states, they are often labeled "Palm and Cactus" mix.

The guys on the other forum came to the right conclusion.

However, there is lots of talk about using sand there. Avoid this unless you are trying to make concrete. Also coir and peat are discussed almost synonymously. They are very different. Coir is suitable as one of the minor ingredients in a soil mix, but peat is just plain awful.

Another thing that stands out as not good about the store mix is the most prominent feature on the bag - "SaturAid Wetting Agent".

[Auxnorm]

Well I guess all this mix was is a waste of money. I think I will just re-pot sooner than I would next time and make sure to buy or make a good quality mix.

The saturaid was in the last mix I used I'm not so worried as very hot weather isn't far off. It's looking like little rain again. The last time I re-potted the drought had been going for a decade.
So I hope for a year or more they might be ok

[SnowFella]

It's kinda hard though to find soil without a wetting agent down here, generally just some small granules designed to hold water in alittle bit longer than just the regular soil.

I use something similar, just a different brand really I'd think. Does have some form of wetting agent although I haven't really noticed any granules in it. Do however contain a fair bit of wood chips that I sift out before using it.

Do however mix it one part soil to one part cource sand and one part perlite. In terracotta pots it dries out real quick.

[iann]

A wetting agent is not the same as a moisture retaining granule.

The wetting agent is a type of detergent to make it easier to have peat, and to a lesser extent coir or bark, take up water after they have been baked dry. Without it, the water just runs straight through or pools on top. So nothing wrong with the wetting agent itself, except that it indicates the bag has the wrong sort of stuff in it

Moisture retaining granules suck up relatively large amounts of water and then release it slowly as the surrounding soil dries out. They expand into gel-like lumps when they are full of water. They aren't as bad as they sound for cacti, because they store the water in a way that doesn't promote rot. They can keep extremely free-draining soils moist for a little longer and give plants a chance to get a drink without ever having to be in a soggy soil. However, a soggy soil plus water retaining granules is a disaster because they will keep the soil soggy for longer. The fired clay granules that many people use do a similar job, but they don't store as much water.

[Auxnorm]

Update

My barrel cactus that I replanted in this awful mix The once healthy root system rotted back leaving a small one not the happiest cactus. I also planted it with the roots as the dangled down so they went way to deep a bad mistake on my part also... the soil retained to much moisture as well and I used a glazed pot.

I'm glad I have learned enough now to hopefully never make a horrid mistake again. I should of went with my gut when I first looked at what the soil mix was like. Now it's re-potted in a suitable terracotta pot and the right soil mix that will make it happy.
I'm just glad I decided to pull it out and do it properly before I lost it and while it still had some roots. It if didn't I think it would of been rotting and I would of had one of my favorite cactus go the way of a dodo.

Happy ending well I think so, though I will know in a few months for sure I guess.