Poet's Narcissus (Narcissus poeticus)
Why we grow it: Also known as poet's daffodil, these pretty white bulb flowers, with a yellow center cup much smaller than the common daffodil's, stand up to deer, rabbits, and voles better than other blooms, making them a prime choice for adding a bit of cheer to your beds.
Deadly parts: The entire plant, especially the bulbs, which are potent emetics, inducing vomiting.
Toxic toll: If the scent of a narcissus bouquet in a closed room is strong enough to cause a headache, just imagine what eating an entire bulb might do. Think severe nausea, convulsions, fainting, paralysis and eventual death. Still want to plant them? Watch any open wounds you may have while tending to them—coming into contact with their bulb secretions has produced staggering, numbness, and heart paralysis.
Photo by Flickr user AnneTanne