August 24 is the feast day of St. Bartholomew, one of the twelve apostles and a martyr.
According to the flower calendar in the Collectanea of V.S. Lean, the sunflower becomes a star for the feast of St. Bartholomew:
"The Old English church recommended decorating with the sunflower on St. Bartholomew's day, 24 August, because it represented constancy and devotion [.]"And Forster says:
"The sunflower is called in the Floral Directory, St. Bartholomew's Star".
See also Gemma's post Summer Yet Solemn for some beautiful sunflower arrangements.
Sources: Forster, Circle of the Seasons (T. Hookham, London, 1828), p. 237. Ward and Lovejoy, A Contemplation Upon Flowers (Timber Press, 1999), p. 347.
Image: A sunflower in Germany, from Wikimedia Commons. Some rights reserved.
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*Some sources substitute "below" and others substitute "flew"



