Why we grow it:An unintended but not uncommon garden trespasser—with its small, white flowers growing in umbrella-like clusters—this perennial doesn't look too menacing. It may be growing on the edges of your property, especially if you live near a meadow, pasture, or stream.
Deadly parts:The whole plant, especially the roots of early growth.
Toxic toll:This wildflower has been dubbed "the most violently toxic plant that grows in North America" by the USDA. True to its killer reputation, water hemlock can strike you dead within 15 minutes of ingestion. The poison cicutoxin wastes no time in attacking the central nervous system, causing severe seizures and convulsions that turn deadly as a result of asphyxia and cardiovascular collapse.
Your garden may be a relaxing retreat, but it's not a place to let your guard down, especially when it comes to small children and your family's pets. Some popular plants you prize for their ornamental beauty can turn into toxic killers within minutes if ingested, whether consumed out of curiosity or by mistake. With this list you'll know what flowers, shrubs and berries to warn young, inquisitive minds about and which bushes and flowers to keep out of paw's reach. You'll also learn the symptoms of poisoning because—after prevention—rapid treatment is the only defense against death. | By Danielle Blundell,This Old House Online Also fromThis Old House: