Paver Flowers - this would be fun with custom middles the kids make (same size as some of the aggregate pavers) with colored glass beads. Fun keepsake stepping stones adding a splash of color in the flower beds. - Flower Beds and Gardens
(I love this plant. Could grow it in OK, but not sure about Colorado?) This attractive form of horsetail (Equisetum) is an invasive spreader, but confined to a planter like this, it's well-behaved AND a cool architectural addition.