I apologize for this delayed reply to your gardening question and hope it is still helpful to you.
I'm sorry but I am not aware of any plant called Red Rhildron. Can you check again for another name or spelling and submit another question. I'm more that happy to try and help if you can come up with another name for this plant so I can know which one you are talking about.
Thanks for the question. Best wishes for a wonderful gardening season. Please stop in again soon!
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