Botanic Garden >> Gardening > >> Question and Answer >> Plant Species >> Roses

Identifying a Mystery Shrub on Mackinac Island

Without a photo, identification is speculative. Your description (large magenta flowers, thorns, rose-like leaves, shrub form) suggests:

Likely Candidates

Rugosa Rose (Rosa rugosa) – large, fragrant, single/semi-double flowers in magenta/pink/white; very thorny; wrinkled leaves; forms large shrubs. See links in original answer for photos.
Rose of Sharon (Hibiscus syriacus) – but flowers are more hibiscus-like, less rose-like.

Next Steps

Compare your memory/photos to rugosa rose images online. Key rugosa traits: wrinkled (rugose) leaves, prominent thorns, tomato-like hips in fall, salt tolerance (common on islands).

Roses: When to Prune a Rose Bush Topiary in Pasadena, CA; Why Your Knock Out Rose Isn't Blooming; Locating 'Leonidas' Rose in the UK: A Florist Variety; Reviving an Old Floribunda Rose That Stopped Blooming: Pruning and Fertilizer Reset; Is My Mystery Rose a Bush or Climber? First-Year Identification Guide; Stopping Invasive Rose Suckers in the Lawn: Rootstock Takeover; Can I Divide a Rose Bush to Make Two Plants?; Saving a Potted Memorial Rose Kept Indoors: Move Out, Prune Hard, Treat Mold; Fall Pruning Tall Roses in Maryland Mountains; Transplanting a Mature Rugosa Rose: Timing and Techniques for Success

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