Scotch Broom (cytisus-scoparius) Siter Rosie(r) - Invasive in Ohio? - Ask Extension
I picked up a Sister Rosie Scotch Broom at Oakland Nursery in Columbu, OH. I hava a perfect spot for it and really want to use it but I have become a...
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Scotch Broom (cytisus-scoparius) Siter Rosie(r) - Invasive in Ohio? #865593
Asked April 23, 2024, 1:12 PM EDT
I picked up a Sister Rosie Scotch Broom at Oakland Nursery in Columbu, OH. I hava a perfect spot for it and really want to use it but I have become aware that there is an issue with the Scotch Broom being considered a noxious weed in the West and PNW.
Is this thing safe to plant in Columbus 6b? It will be in a bed with other specimen plants but I don't want to create a problem fo rmyself and the entire neighborhood.
I have tried to research these other varieties and I don't think these are sterile.
https://www.provenwinners.com/plants/cytisus/sister-rosie-scotch-broom-cytisus-scoparius
Franklin County Ohio
Expert Response
I commend you for your concern for the environment. It is true that Scotch Broom is not currently listed as invasive in Ohio, possibly because we have less of a mediterranean-type climate than the one it is native to. However, from looking at the growing habits of this shrub, it is clear that it has the potential to become invasive here as it is out west.
The reviews on the link you sent me describing the product were interesting--the most positive two were from the same person as were the most negative two. It is likely that your specimen, being a hybrid, will produce LESS fertile seeds than a straight species but is unlikely to be truly sterile. Since the seeds are dispersed by ants, which abound everywhere, it would have the potential to spread. If you chose to plant it (which is certainly legal in Ohio), deadheading and /or pruning it after the flowers have wilted to prevent seed formation would certainly help decrease the chances of it spreading.
The recent decision to list Callery pear as invasive in many states, including Ohio, is a cautionary tale that might apply to the Scotch Broom. These trees were originally thought to be sterile--producing beautiful spring flowers but no "messy" fruit and therefore not spreading. Obviously this was not the case; the white blooms are everywhere and it is now illegal to "sell, grow, or plant in Ohio as of Jan 1, 2023" (Joe Boggs, OSU Extension). Unfortunately, that cat is out of the bag...
You might ask your garden center to contact the producers of this "Sister Rosie" cultivar and ask if tests have been conducted to prove the sterility of the fruit. If no such information is available, I would recommend either exchanging the plant (although it is beautiful) or plan to deadhead/prune the flowers as soon as it is done blooming.
The link below discusses the spread of Scotch Broom in the west, although you seem to be familiar with the problem.
Exotic Species: Scotch Broom (U.S. National Park Service) (nps.gov).
Sorry I don't have an absolute answer about the sterility of the plant; I do appreciate your concern about planting a potentially invasive species.
The reviews on the link you sent me describing the product were interesting--the most positive two were from the same person as were the most negative two. It is likely that your specimen, being a hybrid, will produce LESS fertile seeds than a straight species but is unlikely to be truly sterile. Since the seeds are dispersed by ants, which abound everywhere, it would have the potential to spread. If you chose to plant it (which is certainly legal in Ohio), deadheading and /or pruning it after the flowers have wilted to prevent seed formation would certainly help decrease the chances of it spreading.
The recent decision to list Callery pear as invasive in many states, including Ohio, is a cautionary tale that might apply to the Scotch Broom. These trees were originally thought to be sterile--producing beautiful spring flowers but no "messy" fruit and therefore not spreading. Obviously this was not the case; the white blooms are everywhere and it is now illegal to "sell, grow, or plant in Ohio as of Jan 1, 2023" (Joe Boggs, OSU Extension). Unfortunately, that cat is out of the bag...
You might ask your garden center to contact the producers of this "Sister Rosie" cultivar and ask if tests have been conducted to prove the sterility of the fruit. If no such information is available, I would recommend either exchanging the plant (although it is beautiful) or plan to deadhead/prune the flowers as soon as it is done blooming.
The link below discusses the spread of Scotch Broom in the west, although you seem to be familiar with the problem.
Exotic Species: Scotch Broom (U.S. National Park Service) (nps.gov).
Sorry I don't have an absolute answer about the sterility of the plant; I do appreciate your concern about planting a potentially invasive species.
