Light vs Heat: when to shade greenhouse?

[habitat_gardener]

Originally Posted by Cole_Robbie

There's a few products out for greenhouses that are a "shade paint." They are a white paint that is temporary and easy to wash off.

I have a poly sheeting, aka "greenhouse plastic," over my greenhouse, because it is so much cheaper than the polycarb panels. I tried to make my own shade paint from diluted latex paint, but I couldn't wash it off the following year, even with a pressure washer.

So I use mud. It works just as well...until the rain washes it off. I only need the shade for a few weeks anyway, towards the end of the season. Plus, I get to have the fun of throwing buckets of mud. It feels like vandalism

That sounds like so much fun! I'd be concerned about scratching the plastic (from the sand particles), or having too much fun applying the shade coating and making holes in the plastic. Here, with no summer rain, the mud would stay on the plastic for 6 months. I wonder if that would make the plastic last longer, or degrade it faster.