Flower Of An Hour, Bladder Hibiscus, Venice, Venus Mallow
Synonyms of Hibiscus trionum (25) (Updated from Plants of the World Online on 3-20-21): Abelmoschus collinsianus (Nutt.) Alph.Wood, Hibiscus africanus Mill., Hibiscus cuneifolius Garcke, Hibiscus dissectus Wall., Hibiscus hastifolius E.Mey. ex Harv., Hibiscus hispidus Mill., Hibiscus humboldtii Fisch. & C.A.Mey., Hibiscus humboldtii Schrank ex Colla, Hibiscus marchallianus Fisch. & C.A.Mey., Hibiscus pallidus Raf. ex S.Watson, Hibiscus physodes E.Mey. ex Harv., Hibiscus pusillus Eckl. & Zeyh., Hibiscus ternatus Cav., Hibiscus trionicus St.-Lag., Hibiscus trionum var. cordifolius DC., Hibiscus trionum var. vesicarius (Cav.) Hochr., Hibiscus uniflorus E.Mey. ex Harv., Hibiscus vesicarius Cav., Ketmia trionum (Scop.) Scop., Laguna ternata (Cav.) Willd., Trionum annuum Medik., Trionum cordifolium Moench, Trionum diffusum Moench, Trionum frutescens Medik., Trionum trionum (L.) Wooton & Standl.
Hibiscus trionum L. is the correct and accepted scientific name for this species of Hibiscus. Both the genus and species were named and described as such by Carl von Linnaeus in the second volume of the first edition of Species Plantarum in 1753.
Plants of the World Online by Kew lists 420 species in the Hibiscus genus (as of when Last updated this page on 3-20-21). It is a member of the plant family Malvaceae with 250 genera. Those numbers could change as updates are made.
The distribution map above for Hibiscus trionum is from Plants of the World Online. Areas in green are where the species is native and purple where it has been introduced. The map on the USDA Plants Database for North America is similar. The species could be more widespread than what the maps show.
THERE ARE SEVERAL LINKS AT THE BOTTOM OF THE PAGE FOR FURTHER READING AND TO HELP WITH A BETTER POSITIVE ID.
I found a few of these growing in the garden in 2020 but its flowers were usually always closed by the time I went to work in the garden. The species gets its common name, Flower of An Hour, due to the flowers being only open for a short period of time during the day
The Hibiscus trionum is an easily recognized wildflower that grows in a variety of habitats in fields, gardens, pastures, especially where the ground has been tilled. The species is not native to the United States and was originally brought here as an ornamental. They can become a problem in fields and gardens…
Hibiscus trionum grows in a loose cluster of stems to at least 24” long. The round stems are pubescent (hairy), but the hairs usually fall off as the plant ages.
Missouri Plants says many of the hairs appear branched or fasciculate (closely grouped cluster). The stems may become scabrous caused by the swollen bases of the fasciculate hairs.
What complicated leaves to explain! The leaves are deeply 3-lobed, each lobe being lobed. The leaves grow in an alternate manner along the stems and many have stems growing from the adaxial (where the petiole comes from the stem) at the nodes. Leaves can be scalloped and/or have blunt teeth. The upper surface of the leaves are fairly pubescent (hairy) with normal and fasciculate hairs along the veins. You can read better and more technical descriptions from several of the links below.
Individual flowers emerge on fairly long, hairy petioles from the axils (adaxial) of stem leaves at the nodes.
The flowers are only open for s short period of time during the day. Flowers are around 2” in diameter, have 5 yellow petals, purple at the base. The flower petals are surrounded by a large calyx with 5 segments that enlarge over a few days. The calyx is surrounded by several bracts. Well, there is obviously more to the flower than that but you can read about then from the links below.
The interesting thing about the Hibiscus trionum is how they pollinate. Once the flowers open they are receptive to pollination from bees or other insects. Since the flowers are only open for a short period, they may not get pollinated with the pollen from other flowers. If this is the case, perhaps once the flower closes, the styles in the center of the flower bend to make contact with the anthers to self-pollinate.
In 2021, I will attempt to take better close-ups of the flowers and hopefully find a few seed pods to photograph as well. Maybe I can get some close-ups of the fasciculate hairs. 🙂
I have enjoyed photographing and learning about the many wildflowers growing on the farm and other areas. My farm is in Windsor, Missouri in Pettis County (Henry County is across the street and Benton and Johnson aren’t far away). I have grown over 500 different plants and most have pages listed on the right side of the blog. I am not an expert, botanist, or horticulturalist. I just like growing, photographing, and writing about my experience. I rely on several websites for ID and a horticulturalist I contact if I cannot figure them out. Wildflowers can be somewhat variable from location to location, so sometimes it gets a bit confusing. If you see I have made an error, please let me know so I can correct what I have written.
I hope you found this page useful and be sure to check the links below for more information. They were written by experts and provide much more information. Some sites may not be up-to-date but they are always a work in progress. If you can, I would appreciate it if you would click on the “Like” below and leave a comment. It helps us bloggers stay motivated. You can also send an email to me at firstname.lastname@example.org. I would enjoy hearing from you especially if you notice something is a bit whacky
FOR FURTHER READING:
PLANTS OF THE WORLD ONLINE (GENUS/SPECIES)
INTERNATIONAL PLANT NAMES INDEX (GENUS/SPECIES)
WORLD FLORA ONLINE (GENUS/SPECIES)
USDA PLANTS DATABASE
MISSOURI BOTANICAL GARDEN
KANSAS WILDFLOWERS AND GRASSES
PFAF (PLANTS FOR A FUTURE)
FLORA OF NORTH AMERICA
GARDENING KNOW HOW
NOTE: The figures may not match on these websites. It depends on when and how they make updates and when their sources make updates (and if they update their sources or even read what they say). Accepted scientific names change periodically and it can be hard to keep with. In my opinion, Plants of the World Online by Kew is the most reliable and up-to-date database and they make updates on a regular basis. I make updates at least once a year and when I write new pages but I do get behind. We are all a work in progress. 🙂