Can I color the Durable GreenBed side panels and if so, what should I use?

Yes!  Use a cement stain available at any home improvement center. Custom color for your Durable Green Bed is easy. You can use any cement stain to create a lovely decorative, fun contrasting, or coordinated color for your raised garden beds  The pictured samples were done with the Behr brand of semi transparent cement stains.

stained raised gaden bed panels