Identification of plant in West Norfolk garden
I need identification of a plant in my garden. It has stems that are about 3/4 inch wide that are white with brown spots on them. They are currently about 2 foot tall. The leaves unfurl and the flowers of which there is one per plant are like the cuckoopint. They come up about a foot long and are a deep purple around a black pointed bit. Once the flowers are open the whole plant wilts immediately and within a day look dead. This is my third summer here and the plants are spreading. If they are a rarity I don't want to pull them up. Advice please.