Cat litter

[Jim_Mercer]

I'm a bit limited by what I can move - getting big bags delivered isn't the problem, its getting them where I need them with limited space so would probably have to move them which is OK for small bags but definitely not for large bags of grit or John Innes

I've got a few bits left over from last year and have just got some lava and clay pebbles via Amazon

Sample from everything in picture below and the sieve that I usually use to remove large lumps from the mix. The Westland mix is the old version containing peat which has now been replaced by a peat free mix. The Tesco cat litter from the bottom of the bag seems to be smaller granules than most of the bag. I wasn't expecting The Focus mix to be usable straight from the bag hence the other components. The jondo grit is my last bag from a bulk purchase that was a mix of sizes (and a full bag is too heavy for me to move)

[MatDz]

[...] and have just got some lava and clay pebbles via Amazon

Is this "lava" the Lava-Lite from your photograph? Looks suspiciously white, what it is exactly if you happen to know?

Back to the topic, I am also using 4 main ingredients at the moment, roughly in equal proportions (except when not...):
- Loam based top soil (as a fine inorganic aggregate);
- Peat free ericaceous compost (pH down, some organic content, will probably skip for Lophophoras and similar);
- Fine moler clay (aeration and moisture retention);
- Fine hort. grit.

I quite like how this looks and behaves so far. I also have a bag of pumice, but didn't decide what to do with it yet. Might use it for bonsai Maples...

[SimonT]

It takes a while to test a new compost mix so I just wish supplies would settle down.
There are so many new composts on the market at the moment as it is and lots of old ones are vanishing.
Now molar clay cat litter has gone off the shelves as well.

At the moment I use 2/3 JI and 1/3 drainage which I usually use grit, molar clay and perlite.
I add horticultural sand if I think the mix is too "open".

JI I'm swapping (after testing) for peat free JI or else for loam+peat free as MatDz mentioned.
I'd always planned to get rid of perlite and substitute molar clay for this part, but the one thing about perlite is that it is widely available.
It is light as well come to think about it.

For sulcos or other plants requiring really good drainage, I was just going to reduce the JI component to say 50% or less with the drainage.

[edds]

I use 50:50 JI and Potting grit. I use perlite for my seed mix but really hate the floating bits.

The place lava substrate pictured above looks like pumice. I have two different grades for orchid compost mixtures that look identical.

[MatDz]

I use 50:50 JI and Potting grit. I use perlite for my seed mix but really hate the floating bits.

The place lava substrate pictured above looks like pumice. I have two different grades for orchid compost mixtures that look identical.

Moler clay + JI (or loam and ericaceous now) work perfect for seeds. If I could I'd burn all perlite around for that exact reason.

[edds]

Moler clay + JI (or loam and ericaceous now) work perfect for seeds. If I could I'd burn all perlite around for that exact reason.

I tried that mix and didn't get on with it at all. Felt it dried out too quickly. Perlite / John Innes seems to work best for me with how I grow currently.

[MatDz]

I'm surprised to hear that, clay certainly holds more moisture than perlite in my limited experience. Anyway, if it works, it works!

[Herts Mike]

I use JI and vermiculite 50/50 for seeds. Works perfectly for me.

[tonyironscacti]

Yes, I have used and still use J.I seed compost 50% & Horticultural Vermiculite 50%.

Have tried other mixes but always come back to this one.

[edds]

I've never been able to get on with vermiculite as a compost addition. I think I compress it too much. (Sorry for dragging this off topic.)