A raised and portable salad table would be great for a balcony, rooftop or yard, a good way to grow shallow-rooted leafy vegetables like lettuces, spinach, and other greens.
The simplest designs use either wire or window screen material fixed to a wooden frame. Wooden cross-pieces can be used to add strength, and to divide the frame into compartments. A soil-less potting mix should be used since it's much lighter, and allows the plants roots to breathe better. A mix composed of course material, like perlite, some worm castings and peat moss would also work well.
For wood, 1" x 4" pine is inexpensive and works just fine, however you could also use wood from a pallet. Just be sure not to use treated wood, since this is for consumption!
See many more ideas for Salad Trays and Tables at Grow-it-Organically.
(Images by Steve Masley)
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Maybe THIS is how I could finally grow lettuce without the rabbits munching it into oblivion before I can eat any!
Is there anything on the bottom to prevent the water and soil from seeping through or is something needed to catch the drainage in the bottom?
The University of Maryland has been working for years on popularizing the idea of salad tables (maybe the idea started there? they own and trademark the term "salad table").
They have a great website that details everything including a plans you can download to build your own salad table plus lots of info on growing and care of your crop.
UMD's Original Salad Table
Martha had the UMD professor on her show a few years ago and she has info on her website as well.
Martha's Salad Table
These salad tables were in a lot of press around that time. I'm surprised this hasn't already been covered here! It's a great idea and I wish my husband would build one already like he promised.