I'm head over heels for 'Henna.' Dense and uniform, it needs little pinching and tops out at 24 inches tall. Beautiful serrated foliage is chartreuse and copper above and deep burgundy underneath. Excellent bedding plant; great in pots.
PRESCRIPTION FOR SUCCESS: Full sun gives the brightest colors. Provide moist, fertile, well-drained soil. Feed every three weeks with a liquid 20-20-20 fertilizer. When frost finally kills it in fall, come and cry on Dr. Steve's shoulder. There, there, it's okay.