The International Checklist for Hyacinths and Miscellaneous Bulbs, KAVB, 1991 edition: Hymenocallis 'Sulphur Queen' - narcissiflora (Jacq.) J.F. Macbr. x amancaes (Ruiz Lopez & Pavon) Nicholson Tubergen, 1830; flowers primrose-yellow, 6 per umbel, throat light yellow with green stripes. (2n=74) F.C.C.-R.H.S. 1927 Ernest Chabot in his "How to Grow Rare Greenhouse Plants," published in 1952, lists I. carribaea, winter flowering; I. occdentalis, spring-flowering; I. festalis. He then goes on to mention that "Several named varieties are also available. Sulphur Queen has light yellow blooms of rare beauty." Interesting from an historical perspective, while 'Sulphur Queen' is not mentioned in John C. Wister's "Bulbs for American Gardens," published in 1930, on page 209ff. in the chapter on tender bulbs he mentions Hymenocallis . . . includes Ismene and goes on briefly "Some of them, macrostephana, speciosa, and caribea, are winter blooming, and should be treated like Crinums. They need a warm temperature and should be rested in the summer. Other species such as calathina, Harrisiana, Macleana, rotata and littoralis, require a cooler temperature but still greenhouse and they bloom in the spring and summer and rest in the winter. A few like lacera and galvestonensis are hardy in the Southern States and bloom in the spring." All of which perhaps indicates that this wide range of Hymenocallis / Ismene were to some extent available. Judy in New Jersey where the La Nina summer has settled in with sunshine, high temperatures, and no rain