This is one of my very favourite perennials – euphorbia (cushion spurge). It starts out with the bright yellow/green flowers seen below as it assumes its 2 ft. x 2ft. summer shape of a perfect half dome. Its perfect shape is an accent in your garden during the summer as it just stays green. Come later in the season each flower becomes speckled with yellow and orange buds. Soon the whole plant is afire in a lovely fall colour. It prefers a hot dry sunny spot.