Dietitians are the only qualified health professionals that assess, diagnose and treat dietary and nutritional problems at an individual and wider public-health level. They work with both healthy and sick people.
I have 3 different types of coneflowers: purple, yellow (Goldsturm), and orange (Sunset?). The purple I put in 2 years ago, and just isn't growing. It is still less than 5-6 tall with only 2 leaves, and surprisingly bloomed one pathetic flower. It still looks like the day I brought it home from the nursery.
There are varieties to choose from depending on the height, color, flowering season and length of bloom you want. Examples of perennial flowers include datura plants, lavender, datura and lobelia. Datura plants survive in hot weather conditions and they can even grow as tress.