One of the newest glazing options, UV treated polycarbonate is a rigid plastic
which provides much of the clarity of glass but is stronger and more resistant
to impact than other glazings. Polycarbonate comes in multiwall panels with many
structural walls separating its two or more flat sides (looks similar to cardboard
in design when viewed on edge). This structure gives it greater strength
and superior heat retention with the insulating air space built into the product. Multiwall
polycarbonate also provides your greenhouse with an even diffused light which
is optimal for growing plants. Another advantage of polycarbonate is its long
lifespan.
[A] - The first picture shows light passing through a clear covering. They
do not diffuse light well causing sharper darker shadows to appear. This is less
optimal for growing plants, but great if you want a clear view of the outside.
[B] - The second picture shows light passing through a diffuse covering like multiwall
polycarbonate. When light passes through, it scatters causing shade to be "lighter".
Plants in the shade receive more total light. This creates better growing conditions
for the whole plant.