DIY Vertical Cinder Block Planter: Urban Garden Style in an Afternoon

Cinder block planters are trending—we took ours vertical for a space-saving, customizable weekend project. Design first (we dry-fitted at Home Depot), buy extra blocks for flexibility, and cap planting cavities with metal flashing + landscape adhesive.

Supplies

• Cinder blocks (dual & single cores; we used 5 dual, 2 single).
• Pre-cut metal flashing rectangles (roofing dept, ~$0.59 each).
• Loctite PL 375 heavy-duty construction adhesive + caulk gun.
• Lightweight potting soil + 4-in. plants (sedums, lavender for sun; ferns/mosses for shade).

Build Steps

1. Cap the planter cavities: Generous ¼-in. adhesive bead on block, press on flashing, wipe excess (doesn't dry clear). All four sides must bond for security.
2. Weight while curing: Flip capped blocks onto newspaper (cap down); block weight ensures adhesion.
3. Assemble (two people): Follow design photo. Apply adhesive, place blocks, have partner hold until upper weight stabilizes lower courses.
4. Plant: Lightweight mix + 4-in. starts. Sedums love the porous blocks.

Cool urban aesthetic, fully customizable—pin the final photo to save the idea!