This perennial of a different colour is sure to put a smile on your face. In midsummer, tall stems emerge from mounded, grasslike foliage to show off flower spikes filled with limegreen buds. Within days, the buds open from the base upward to reveal bright yellow blooms in a truly unique flower form. The single blooms last for a very long time in the garden, attracting butterflies and hummingbirds to the area. Great for cutting, too.Kniphofia