Soil Substrate Comparison: Water Retention

Bonsai Soil Tests: Part 1: Water Retention

Note:
Retention Values (g @ %) given after 5.25-hour
Rank given for 24-hour Retention based on values.

Organic Rankings:
1. Coconut Coir: 129g @ 14.57% loss
2. Pine Bark: 22g @ 14.86% loss
3. Compost: 26g @ 31.58% loss
4. Commercial Peat Moss: 6g @ 40% loss

Inorganic Rankings:
1. Diatomaceous Earth: 37g @ 30.19% loss
2. Akadama: 22g @ 26.67% loss
3. Pumice: 22g @ 29.03% loss
4. LECA (Turface): 30g @ 36.17% loss
5. Vermiculite: 28g @ 41.67% loss
6. Perlite: 14g @ 36.36% loss
7. Sand: 12g @ 67.56% loss
8. Lava Rock (Scoria): 4g @ 76.47% loss
9. Expanded Shale: 2g @ 84.62% loss
10. Granite Chips: 1g @ 94.44% loss

Quick Correction: Diatomaceous earth is not calcined clay, like Oil-Dri. It is silica based, formed from fossilized algae.