Until recently, Egyptian onion has been considered a variety or cultivar of common onion A. cepa. As of spring 2026, four observations from Massachusetts at iNaturalist were identified as A. ×proliferum, and at least one of those could not have been planted. Differently from A. cepa, it produces bulbils instead of flowers (in addition to other differentiating characters). It is considered very hardy and can be established vegetatively.