Greenhouse Gardening – alternatives to glass

Glass is the traditional material for greenhouses, for many reasons, but it is also relatively expensive, heavy, and brittle and can cause injuries especially if there are children using the garden or people whose balance is not good or whose mobility may be limited.

Plastic materials can offer an alternative. Double-layered polycarbonate is relatively costly and transmits slightly less light than glass . It is a material that degrades in sunlight over the years and can be prone to scratches, but makes a rigid, well-insulated, safe, and vandal-proof covering, that gives results that are comparable to those of growing under glass.

Single layered sheets of polycarbonate or acrylic sheets may flex, loosen and blow away in gales. They are also poor insulators, although it is definitely the case that they are relatively inexpensive, this may be the ideal solution for the short term.

Robust, polythene covered poly-tunnels are sold for garden use, and can be covered with films treated in ways that make them nearly as efficient as glass. Tunnels offer an economical alternative to unheated greenhouses but can be difficult to get into and out of for those with limited mobility.

Greenhouse gardening polytunnel photograph by mike warren, used under a creative commons attribution licence