J L.

Tried spray on interior of a decorative wood bowl to use as a planter for hens & chicks. I waited 3-4 days to be sure of thorough dry time, prior to adding soil and plants. Within 1-2 weeks dirt, plants were covered in mildew (whitish/grey fuzzy powdery). Because the plants are succulents I didnt water much at all, yet mildew covered soil & plants, and plants were turning black and dying. Had to throw out plants and soil. Photos show mildew on bowl.
Later we decided to try a small can of liquid rubber before spending $90 for a gallon. Planned to use it for waterproofing a plywood roof for a doghouse. I even called Flex Seal company to verify use and was assured it would work and would not mildew. I never got a chance to see if it would mildew like spray, but did try it on a scrap piece of plywood. Over 48 hours later, (recommended cure time), I tested with finger and then fingernail. The thinner area rolled right off wood and fingernail easily scratched thicker area off.
Not sure what others might use these products for, but I would highly recommend testing first. Both products were a waist of money for both projects. Hope this helps anyone thinking of using for similar projects.