vermiculite on Universal
Quick answer
If your Universal has vermiculite, the most likely cause is: Vermiculite is a hydrated magnesium-aluminum silicate mineral expanded by heating, creating accordions-shaped particles with 30-40% water retention and 25-30% air porosity. It has a high cation exchange capacity (CEC: 100-150 meq/100g) making it excellent for nutrient retention. pH is slightly alkaline (7.0-9.0) depending on grade.
Start here:
- 1. For moisture-loving tropicals (ferns, prayer plants): add 20-30% coarse vermiculite to boost retention
- 2. For seed starting mixes: use 50% vermiculite with 50% peat for consistent moisture around seeds
Why Universal gets vermiculite
Vermiculite is a hydrated magnesium-aluminum silicate mineral expanded by heating, creating accordions-shaped particles with 30-40% water retention and 25-30% air porosity. It has a high cation exchange capacity (CEC: 100-150 meq/100g) making it excellent for nutrient retention. pH is slightly alkaline (7.0-9.0) depending on grade.
How to reverse vermiculite on Universal
- 1
For moisture-loving tropicals (ferns, prayer plants): add 20-30% coarse vermiculite to boost retention
- 2
For seed starting mixes: use 50% vermiculite with 50% peat for consistent moisture around seeds
- 3
For hanging baskets: add 15-20% vermiculite to reduce watering frequency
- 4
Combine vermiculite with perlite (1:1 ratio) to balance moisture retention with aeration
Keep vermiculite off this Universal
Do not use fine vermiculite for succulents as it retains too much moisture. Use coarse grade for moisture-loving plants and seed starting. Vermiculite compacts over time — mix with perlite to maintain long-term aeration.