Monrovia does grow Spanish Broom but it is a wholesale nursery. Their plants are available only through local retail garden centers.
Check out the following web site. It has a box for you to enter your zip code and will then give you a list of local retailers that carry Monrovia plants. Perhaps one of them can get the Spanish Broom for you.
I looked for a mail order source but was not able to find any.
Thanks for the question. Please stop in again soon!
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