Oh, it’s a long, long time from May to December
But the days grow short when you reach September
And as the days grow short, the goldenrods burst into bloom. At the same time, hay fever afflicts the allergic. The goldenrods are the showiest, most visible plants of the season, and they are all over the place. So people take concurrence to be causation, and blame the goldenrods. But it’s not their fault.
On the plants, from Wikipedia:
Solidago, commonly called goldenrods, is a genus of about 100 to 120 species of flowering plants in the aster family, Asteraceae. Most are herbaceous perennial species found in open areas such as meadows, prairies, and savannas. They are mostly native to North America, including Mexico; a few species are native to South America and Eurasia.
… The many goldenrod species can be difficult to distinguish, due to their similar bright, golden-yellow flower heads that bloom in late summer. Propagation is by wind-disseminated seeds or by spreading underground rhizomes which can form colonies of vegetative clones of a single plant. They are mostly short-day plants and bloom in late summer and early fall. Some species produce abundant nectar when moisture is plentiful, or when the weather is warm and sunny.
… Goldenrod is often unfairly blamed for causing hay fever in humans. The pollen causing these allergy problems is mainly produced by ragweed (Ambrosia sp.), blooming at the same time as the goldenrod, but is wind-pollinated. Goldenrod pollen is too heavy and sticky to be blown far from the flowers, and is thus mainly pollinated by insects.
… Goldenrods are, in some places, held as a sign of good luck or good fortune. They are considered weeds by many in North America, but they are prized as garden plants in Europe, where British gardeners adopted goldenrod long before Americans did as garden subjects. Goldenrod only began to gain some acceptance in American gardening (other than wildflower gardening) during the 1980s.
They have become invasive species in other parts of the world, including China; Solidago canadensis, which was introduced as a garden plant in Central Europe, has become common in the wild, and in Germany is considered an invasive species that displaces native vegetation from its natural habitat.
There are a fair number of cultivars, including hybrids in several colors, of varying heights and habits, including some not especially given to forming large clumps, so not invasive.
And then on the true culprit in hay fever, again from Wikipedia:
Ragweeds are flowering plants in the genus Ambrosia in the aster family, Asteraceae. They are distributed in the tropical and subtropical regions of the New World, especially North America, where the origin and center of diversity of the genus are in the southwestern United States and northwestern Mexico. Several species have been introduced to the Old World and some have naturalized.
Other common names include bursages and burrobrushes. The genus name is from the Greek ambrosia, the “food of the gods”.
Ragweed pollen is notorious for causing allergic reactions in humans, specifically allergic rhinitis. Up to half of all cases of pollen-related allergic rhinitis in North America are caused by ragweeds. … Ragweed pollen is a common allergen. A single plant may produce about a billion grains of pollen per season, and the pollen is transported on the wind.
An Ambrosia psilostachya plant:
They are geerally inconspicuous plants, weedy rather than showy.
The music. From Wikipedia:
“September Song” is an American pop standard composed by Kurt Weill, with lyric by Maxwell Anderson, introduced by Walter Huston in the 1938 Broadway musical Knickerbocker Holiday. It has since been recorded by numerous singers and instrumentalists. It was also used in the 1950 film September Affair, and for the credits in the television series May to December (a quote from the opening line of the song).
There are many fine recordings, but this one, by Lotte Lenya (Weill’s wife), is my favorite: