Answer: There are quite a few plants that bloom exclusively at night and without a more complete description of the plant, I'm afraid I cannot positively identify your friend's plant. However, here are a few of the night blooming plants that are commonly grown, along with their descriptions. Maybe this information will help ou determine just which plant your friend is growing:
Evening Primroses: (Oenothera ) are perennials with sweetly scented blossoms of soft white, pink and bright yellow that open each evening.
Moonflower: (Ipomoea alba ) is a night-blooming relative of the morning glory that perfumes the garden with five- to six-inch white flowers.
Angel's Trumpet: (Datura innoxia ) produces fragrant, six-inch white flowers that appear from midsummer until frost on this viney annual. Note that this plant is poisonous and should be kept away from children.
Night Phlox: (Phlox 'Midnight Candy' ) at dusk, flowers open to release a honey/almond/vanilla fragrance.
Evening Stock: (Matthiola incana ) has small pink or purplish flowers that are not showy, but emit an intoxicating fragrance at night.
Four O'Clock: (Mirabilis jalapa ) is a sweetly fragrant annual with colorful trumpet-shaped flowers that open in late afternoon and release a jasmine-like perfume.
Nottingham Catchfly: (Silene nutans ) offers a scent reminiscent of hyacinths. The flowers open on three successive nights before fading.
Daylilies: (Hemerocallis ) that bloom at night include 'Moon Frolic' and 'Toltec Sundial'.
Yucca: (Yucca filamentosa ) bears flowers that are open both day and night.
Hope this information helps!
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