For those interested in soilless mixes, perlite and vermiculite are well researched alternatives to peatmoss in a growing capacity. Both Perlite and Vermiculite are inert and have nuetral pH levels.
Properties of Perlite and Vermiculite
- Porous texture
- Liquid retention
- Air circulation
- Low density; cannot be compacted
Perlite (white) is a volcanic rock from the family of amorphous silica. During dilation (the heating process) perlite particles form white granules with minute cavities and pores. This porous texture retains water and fertilizers — which allow plant roots to thrive. They provide optimal irrigation, drainage and aeration due to the non-compressible and irregular feature.
Horticultural Applications of Perlite
1. Soil improvement and conditioning
Useful in soil conditioning concerning optimal moisture retention, improved aeration and drainage as well as the ability to control weight and temperature variations.
2. Irrigation of heavy soils
Eliminates surface cracking and water accumulation to hard, compacted clay soils.
3. Growing Mixes
Provides soil aeration and optimal moisture retention; thereby allowing easy penetration of root systems to achieve maximized growth
4. Conservation of bulbs and root-plants
Perlite's insulating capacity makes it an ideal candidate for the conservation of bulbs and root plants over long periods of time.
Vermiculite (brown) refers to a small group of minerals resembling the lamella structure of the micas. The exfoliation process creates a superior moisture retention property in the material, as well as superior aeration.
Horticultural Applications of Vermiculite
It's lightweight nature allows easy application to cover seedbeds. This cover protects seeds while retaining water and fertilizers needed for their early developmental stages.
2. Hydroponic systems and greenhouses
Exfoliated vermiculite is perfectly adapted to greenhouse cultures and hydroponic systems due to its properties listed above.
3. Cutting and root growth
The main use of vermiculite is its beneficial nature to seedling growth. Space is created for needed root development, providing essential elements to developmental growth.
4. Potting and Planting out
Vermiculite's low density allows ease of handling due to its low density. It's intrinsic properties cushion the transition shock and may reduce the transportation costs per weight.