perlite on Universal
Quick answer
If your Universal has perlite, the most likely cause is: Perlite is a volcanic glass expanded by rapid heating to create white, lightweight granules with 30-40% air porosity and <5% water retention. It contains no nutrients and is pH neutral (7.0). The air channels created by perlite are permanent and do not collapse over time, making it ideal for improving soil structure in container media.
Start here:
- 1. For succulents/cacti: add 40-60% perlite for fast-draining mix
- 2. For aroids and tropicals: add 20-30% perlite to standard potting mix
Why Universal gets perlite
Perlite is a volcanic glass expanded by rapid heating to create white, lightweight granules with 30-40% air porosity and <5% water retention. It contains no nutrients and is pH neutral (7.0). The air channels created by perlite are permanent and do not collapse over time, making it ideal for improving soil structure in container media.
How to reverse perlite on Universal
- 1
For succulents/cacti: add 40-60% perlite for fast-draining mix
- 2
For aroids and tropicals: add 20-30% perlite to standard potting mix
- 3
For seed starting: mix 50% perlite with 50% peat or coir for optimal germination aeration
- 4
Perlite particle size: use coarse grade (3-6mm) for drainage, fine grade (1-3mm) for seed starting
Keep perlite off this Universal
Do not use unwashed perlite near fluoride-sensitive plants like Dracaena as it can contain fluoride residues. Pre-rinse perlite before mixing to remove dust and soluble salts.