For long-lasting, eye-catching summer flowers, coneflowers are a natural choice. 'Sombrero Lemon Yellow' echinacea bears bright yellow flowers on upright stems about two feet tall, the perfect height for container planters and along borders in sunny gardens. Once the flowers start coming, it's fascinating to watch them evolve from a daisy-like form into the characteristic coneflower shape, with a prominent eye and downward drooping petals. Coneflowers thrive in warm summer weather, yet keep on keeping on right up until a hard freeze. Echinacea is a great addition to cut-flower gardens and is fairly drought tolerant, once established.