Maggie Lidz, Winterthur’s estate historian and curator of garden and estate objects writes:
There is a wonderful surprise for anyone who climbs the staircase up to the East Terrace on a sunny winter day. A soil pocket in the staircase wall allows the sweetly fragrant Winter jasmine (Jasminum nudiflorum) to spill down the staircase wall. This yellow-flowered plant, more often found further south, is warmed by the wall and protected from wind by the weeping Norway Spruce. There has been a winter blooming jasmine at Winterthur since at least 1918 and as it usually begins to bloom beginning in late Christmas, seems to signify Christmas on the property.
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Jasmine bloom quotes from H.F. du Pont:
Dec. 25, 1918, Garden Diary: Spring snowdrops for past week. Jasmine also.
Dec. 28, 1940, to his landscape architect Marian Coffin: The weather has been springlike with golf everyday— jasmine blooming on the limestone coping of the steps, …. We have in the house now big branches of Apple Blossom Pyrus and of red Pyrus, vases of spirea arguta, two kinds of Hamamelis, Viburnum fragrans and Jasmine.
Dec. 30, 1946 to his sister Louise: Before Christmas I picked some snowdrops and the house is full of three kinds of hamemelis, jasmine, lonicera etc.
Jan. 14, 1950 to Nell Montgomery (Mrs. Robt.) HF 350: We have had a perfect winter with the Hamamelis Mollis and Jasmine Nudiflora absolutely in full bloom for the last ten days and very beautiful.

[...] For more info about Jasmine and Galanthus in the Winterthur Garden, please see Maggie Lidz’ blog entry: http://gardenblog.winterthur.org/2011/12/15/jasmine-in-bloom/ [...]