moonflower

Ipomoea alba Any of several plants that flower at night:
puhekieltä The ox-eye daisy, Leucanthemum vulgare (defdate)
The corn marigold, (taxlink).
Any of several vines of the genus Ipomoea, especially (taxlink). (defdate)
1977, (w), A Savage War of Peace, New York Review Books 2006, p. 46:

Hôtel Saint-George … through whose exotic gardens of giant contorted euphorbia and sweet-smelling moonflowers Churchill and the titans of the Second World War strolled, laying plans for a world in which Anglo-Saxon predominance seemed assured in perpetuity.