How do I use a pallet as a garden box
I would take the pallets apart, remove the nails and then use the long boards to assemble garden boxes like these:
Since pallet boards are somewhat narrower than the deck boards we used, I'd suggest making it 3-5 board widths tall.
There are several Hometalk members who have created pallet garden designs. Check out this link to see if one of them inspires you. Wishing you the best.