youth-and-old-age

[ yooth-uh n-ohld-eyj, -uh nd ]
/ ˈyuθ ənˌoʊldˈeɪdʒ, -ənd /

noun

a stiff-growing, erect composite plant, Zinnia elegans, of Mexico, having large, solitary flowers with yellow-to-purple disks and usually red rays.

Origin of youth-and-old-age

An Americanism dating back to 1890–95