Valentines Day Yard Sign Letters - We Love You Gnome Yard Decorations for Happy Valentine's Day Party Outdoor Yard Décor with Metal Stakes. Economical and durable, our Coroplast Yard Signs are a staple of outdoor advertising. This outdoor Valentine's Decorations We Love You Gnome Yard signs with Stakes full color direct printed graphics are vertically fluted for use with a Stakes. Coroplast is typically used for yard, parking, real estate, and election signs. They are waterproof.