Don't know anything about Roman Chamomile, but I planted some woolly thyme last fall, along with other thyme (pink chintz) - and whereas they are all healthy, the woolly thyme really took off splendidly to cover a much larger area (maybe about 2 feet in diameter, from a plug size that was planted) - I like it too as it's a gray-green, not bright green. Doesn't flower (since I've had it anyway), and is very low maintenance. I'm getting some more this fall.