Hello and Welcome to the Forums!! I like to build the stands that my screen enclosures sit on. Here is a pic of one I did not too long ago. Nothing fancy, just wanted to hide all the drainage and pots from view. I also wanted something on caster wheels so I could move the entire enclosure out onto the back deck on optimal days. Some prefer to use wire racks that are purchased from Costco, Home Depot or Lowes. They work well because you can simply place a catch basin under the bottom rack. I'm sure there are loads of ideas for drainage issues throughout the plethora of threads in this forum. Give it a good look and I'm sure you will find an idea that suits your needs.
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