Even when the leaves dry up, they never lose their fragrance for years.
This small plant grows fast. Keep cutting the top leaves for use. It keeps growing for a few months. So there is no need to cut from the roots.
Several species yield essential oil and some are used as fodder.
To turn the grey hair into black rub the paste made with the leaves of Artemisia pallens (Dhavanam) and Hibiscus and take bath after sometime.