I sometimes forget to check to see if the flowers of bulbs are fragrant, although some are so obvious one couldn't overlook them. There are many members of the genus Oxalis that are quite fragrant, but being small and at foot or waist level, you usually need to pick up the pot to realize this.
I have one Oxalis in my collection labeled Oxalis fragrans, seen here to the left. This may not be the correct name, but this plant has been in circulation for quite a long time with that moniker. It is indeed fragrant, and a pot can fill a room with its scent, a strong heavy scent like freesias. The flowers open in the afternoon, and stay open into the evening, closing around midnight, quite oblivious to whether the sun is shining or not. This probably indicates a night-flying pollinator. This is a wonderful Oxalis to bring into a room, scenting it in the evening hours.
Oxalis cathara, a rare species from a restricted area of Namaqualand in South Africa, behaves the same way, and has a strong sweet scent. Here it is to the right.
One of the earliest blooming Oxalis is Oxalis commutata. It can bloom as early as August, and has a sweet scent like baby powder. It too is from the Cape Province of South Africa, and is seen here below and to the left.
Oxalis obtusa is my favorite species, with its wonderful range of color and delicate veining of the petals. When color is used to attract pollinators, scent seems superfluous, but I do have one O. obtusa in my collection that is scented like violets. Here it is to the right.
In the catalogue it is called Oxalis obtusa Polished Copper.
Another South African is Oxalis callosa, a beautiful species with purple flowers banded deep crimson in the throat. It, too, has a sweet fragrance. Here it is to the left.
Oxalis pocockiae, seen here below and to the right, has white flowers with a fragrance like fresh coconut. It is also South African.
South America has hundreds of Oxalis species, although most are not as showy as the South African ones, and many are not bulbous. One that has been in cultivation for a very long time is Oxalis lobata, with masses of brilliant yellow flowers that are strongly scented like honey. Here it is to the left.
There are many others that are scented, and I have picked only the most obvious ones. The late Michael Vassar thought that about half of the South African species have some scent, but I think he had a better nose than I do. I will try this season to evaluate all of them for scent, and keep you posted.
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