Thanks for starting this. Here are some of my soil mixes for cacti.
Seed starting mixes:
#1
- 80% washed sand
- 20% worm castings (Sand is washed and sterilized then worm castings added)
#2
- 1 part Seed starting mix (or cacti mix/potting soil)
- 1 part pumice
- 1 part washed sand
Pereskiopsis soil mix:
- 4 parts fox farm soil
- 2 part worm castings
- 2 part pumice
- 1 worm castings
Trichocereus mix:
- 4 parts soil mix
- 4 parts pumice
- 1 part coarse washed sand
Mineral mix:
- 4 parts pumice
- 2 parts washed coarse sand
- 1 part pea gravel
- 1 part coco coir
- .5 part worm castings
- 1 small scoop of slow release ferts
(this isn't exact, I wing it sometimes. I'll try to get a more precise ratio for you guys and then edit this)