araceae bad cabbage creepy England flower garden green Lysichiton malodorous odd plant pungent skunk smelly spadix spathe spike stink strange Sussex unusual weird yellow leaf leaves alien appearance black-flag black-flag-iris blooms bright budding buds bush bush-plant colored colorful coloring colors coloured colourful colouring colours display displayed ferraria-crispa ferraria-undulata flora flowers foliage garden-escape greenery introduced-species invasive iris-family malodorous-cormous-perennial mixed nature nectar pest plants shape shapes Sizes spring unusual-shapes weed Western-Australia