Hey, Joe (waving) - There is no sand or vermiculite in the original gritty mix recipe. Too, you often won't know when or where an appropriate bark product will turn up. For the gritty mix, pine or fir bark that passes 1/4" screen but doesn't pass 1/8" is best, but using up to 3/8 size is ok if it means you'll not have to discard a high % of the bark you're able to find.

The concept that drives the gritty mix is based on a soil that has a fairly consistent particle size, with the soil holding virtually all of it's water within soil particles, on the surface of soil particles, and at the interface where particles touch each other (not in the air spaces between particles). Being particular about particle size ensures there is only air in the large pores between soil particles. When soil particles are too small, or a fraction of small particles is mixed with larger particles, the smaller particles simply occupy the large spaces between large particles, undoing the reason you decide to make the gritty mix in the first place. It doesn't make sense to go to the effort and expense of preparing the soil if you're not going to take advantage of the concept that inspired it. IOW, the sand would wreck the aeration and drainage that was the reason for making the soil to begin with.

Al

That makes perfect sense, which threw me for a loop when I saw the list (wrong list apparently). So, all I need now is where to find screens and a miracle in Alabama to find the bark.

I don't think the bark should be terribly hard to find. Before southern yellow pine is sawed and pressure-treated, it's skinned (debarked) and the bark chipped. That's the stuff you'll be looking for.

Gran-I-Grit (you want "grower" size) is mined in NC, which isn't THAT far away, though I don't think it's readily available in FL. If you can't find Gran-I-Grit, use MannaPro poultry grit or if you're lucky enough to find it - #2 cherrystone/ quartzite.

That list came from a post that's really old. I was trying to help a lady who was absolutely certain she needed more water retention than could be built into the soil by simply varying the ratio of Turface to grit. She didn't, but hadn't had any experience with the soil and had been influenced by others who also felt sure that because water seems to run right through it, that it doesn't retain hardly any water. Even in the dry winters and with my plants under lights and in small pots, I only water 95% of my actively growing plants every 5 days.

Good luck!!

Al

I don't think the bark should be terribly hard to find. Before southern yellow pine is sawed and pressure-treated, it's skinned (debarked) and the bark chipped. That's the stuff you'll be looking for.

Gran-I-Grit (you want "grower" size) is mined in NC, which isn't THAT far away, though I don't think it's readily available in FL. If you can't find Gran-I-Grit, use MannaPro poultry grit or if you're lucky enough to find it - #2 cherrystone/ quartzite.

That list came from a post that's really old. I was trying to help a lady who was absolutely certain she needed more water retention than could be built into the soil by simply varying the ratio of Turface to grit. She didn't, but hadn't had any experience with the soil and had been influenced by others who also felt sure that because water seems to run right through it, that it doesn't retain hardly any water. Even in the dry winters and with my plants under lights and in small pots, I only water 95% of my actively growing plants every 5 days.

Good luck!!

Al

Turns out I already had grani-grit grower size, picked up MannaPro at Tractor Supply and found out after. Another thread solved the bark problem. tcleigh made a thread about her first gritty mix and she bought presorted Repti Bark (fir). I have a three day weekend and look forward to my first mix. Even building a screener like she did. This forum is truly the best.

Thanks for the help Al!