If you are going to transport nursery stock efficiently, then you'll need some racks for flats of 4-inch pots, etc. Here's a pair of racks I built a year ago. The frames are 2x4's, the support rails are 2x2's, and the side guards are 4x3/4. Each level holds six 17-inch flats, so that's a total of 36 I can take to the market - unless of course there's one on my lap, another in the passenger seat, and so on!
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