From T.F. Thiselton Dyer’s Folk-lore of Plants, 1889, p.217:

‘According to an old adage the laurustinus [Viburnum tinus], dedicated to St Faine (January 1), an Irish abbess in the sixth century, may be seen in bloom –

Whether the weather be snow or rain,                                             We are sure to see the flower of St Faine;                                                          Rain comes but seldom and often snow,                                                                   And yet the viburnum is sure to blow’.

Image:  cultivated, Dulwich Park, London Borough of Southwark, December 2020.

Edited 8 December 2021.