I have a home greenhouse attached to our home. I was thinking about removing the existing shade cloth and replacing it with sunblock film on the upper glass panels. I grow a variety of foliage plants and it is partially shaded by trees as well. Most of these products block 99 percent of the UV light. Does this matter and what percent sun block should it get? I now have about 40 per cent blocked plus the trees. I live in the Atlanta, Georgia area.
Where I used to work, we raised mostly bedding plants in a nursery about 50 miles north of Atlanta, Georgia (putting us a little north of the 34th parallel). We covered our greenhouse with shade cloth at the spring equinox and removed it at the autumn equinox. I don't have a record of how much light we blocked, but it was probably about 40%.