Why does asparagus make urine smell Are there any other Spear Grass can cause a noticeable smell within your pee. It is widely known that consuming this verdant plant can result in a powerful fragrance while visiting the bathroom. If you observe an offensive smell following a delicious dish containing asparagus, there's no need to worry. It is simply a typical reaction that occurs internally. Be reassured that the odor is harmless and will go away gradually.