PlantFiles: Your plant database
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From the web site...
Welcome to PlantFiles, the largest plant database in the world with 89,058 entries, 60,013 images and 35,423 comments. Currently entries are from 352 families, 3,345 genera, 3,364 species, and 61,401 cultivars. PF continues to grow through the collaborative efforts of 9,197 gardeners from around the world, most notably the Uber Gardeners. "