A modular planter assembly having plural U-shaped planting containers including plural male open ends, drain holes in a bottom portion thereof and an underneath male drain channel, plural connectors having U-shaped cavities at each end and an underneath drain cavity with seal means disposed therein. The male open ends are secured within the U-shaped cavities and the drain channels are secured within the drain cavity of the connectors. Plural U-shaped end caps having U-shaped cavities with an underneath drain cavity with seal members disposed therein. Opposite male ends are secured within the end cap cavities and the male drain channel is secured within the drain cavity of the end caps forming a single planter assembly with a continuous drain channel to a drain adapter in the end caps to release excess water there from. Plural U-shaped brackets disposed about the containers to support and attach to an elevated wall structure.