Weird is relative. What seems weird to me might not seem weird to you. In the plant kingdom, however, there are definitely some species that most people would acknowledge are highly unusual.
1. Rafflesia arnoldii: this parasitic plant develops the world's largest bloom that can grow over three feet across. The flower is a fleshy color, with spots that make it look like a teenager's acne-ridden skin. It smells bad and has a hole in the center that holds six or seven quarts of water. The plant has no leaves, stems, or roots.
2. Hydnora africana, an unusual flesh-colored, parasitic flower that attacks the nearby roots of shrubby in arid deserts of South Africa. The putrid-smelling blossom attracts herds of carrion beetles.
Image Credit: Martin Heigan (via creative commons)
3. Dracunculus vulgaris: smells like rotting flesh, and has a burgundy-colored, leaf-like flower that projects a slender, black appendage.
4. Amorphophallus: means, literally, "shapeless male genetalia." The name comes from the shape of the protruding black spadix.
