What is perlite primarily used for in greenhouse management?

Perlite is primarily used in greenhouse management to provide good aeration and drainage in growing mixes. This lightweight volcanic glass material has a unique structure that allows for substantial air space between particles, ensuring that roots have access to adequate oxygen while preventing waterlogging. The porous nature of perlite helps improve drainage, which is crucial for preventing root rot and other moisture-related issues.

When mixed with other substrates, perlite enhances the overall physical properties of the medium, supporting healthy root development, which is essential for plant growth. Good aeration is particularly important in greenhouse environments, where plants are often grown in constrained conditions, making perlite an ideal choice for seed starting and potting mixes.

In contrast, while other options involve important aspects of plant growth, they do not accurately depict the primary function of perlite in greenhouse management. For instance, perlite does not serve as a water-retaining substrate, a source of nutrients for plants, or as a means to increase soil bulk density. Instead, its unique characteristics specifically enhance aeration and drainage, making it a preferred agri-mineral in greenhouse applications.