lush flower bed with sage blue and purple flower combined with yellow ornamental grasses lush green color perennial prairie flower

aroma bed bloom blue bunch cluster color combined field flower flowers fluffy garden gaura grass grasses gray green herb kniphofia kobold lavender liatris lily lindheimerei lush nature nemorosa oenothera orange ornamental patio perennial plant prairie purple roof sage salvia sanquisorba spicata spike summer top torch tritoma urban uvaria vertical violet yellow