How can I build a raised planter of three tier of railroad ties?
Cut and stack them," staggering" the corners, so you don't have joints lining up from one tier to the next. Use pieces of PT decking or 2x4 standing verticle on the inside to lock it all together with screws. you can also drill holes through the 3 tiers and pound some rebar through it all, into the ground to help keep it together in place
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