Hieronymiella is a little-known genus in the family Amaryllidaceae from semi-arid and arid regions on the eastern side of the Andes of northwestern Argentina and occasionally in southern Bolivia. The taxonomic treatment of this genus can be found on this PBS thread. DNA sequencing has found that it is a member of the Eustephieae tribe, sister to Chlidanthus, Eustephia, and Pyrolirion. The following cultivation information was provided by Mark Wilcox on the PBS list: Germinated seeds were planted in a 4-inch pot of Schultz's Professional Potting Soil Plus. The plants were grown under two 40 watt fluorescent bulbs for 16 hours each day. Average summer temperatures of ~75-80 °F (23-27 °C) and winter temperatures of ~65-73 °F (18-22 °C). Fertilization was performed for most watering from the bottom with a solution of 1/4 teaspoon of MiracleGro for Roses (18-24-16) to one gallon of water. Allow the soil to dry out between watering.
Hieronymiella aurea Ravenna is native to Salta Province, Argentina. The photos below were taken by Mariano Saviello from habitat.
Hieronymiella clidanthoides Pax is native to Catamarca Province, Argentina. The photos below were taken by Mariano Saviello from San Luis, Argentina.
Hieronymiella marginata (Pax) R.E.Fr., formerly and seemingly again in 2023 known as Hieronymiella argentina (Pax) Hunz. & S.C.Arroyo, occurs on parched, rocky terrain in extreme northern Argentina at altitudes nearing 3000 meters. In habitat, blooming occurs in November and December, just before the arrival of rains. On specimens shown by Arroyo-Leuenberger and Leuenberger (Herbertia 58, pp. 23-45, 2003-2004) basal leaf growth is present with bulbs in full bloom. Unlike them, the specimens shown here were hysteranthous, with no sign of leaf emergence during blooming. Also, coloration was uniquely orange, while the reference article reports other shades for this species. Photos 1-2 taken by Andrew Wilson. Photos 3-4 by Martin Bohnet show a plant with leaves present at flowering in a middle-European climate - one can speculate that the presence of water decides this. The source for this advised to lift the deep seated bulb in fall and replant in spring, but this proved unsuccessful for him - the plants stopped flowering and one took the damage from digging up badly. Growing them instead in a deep pot and removing top soil down to the basal plate but keeping roots undisturbed for (barely) frost free winter storage resulted in the return of flowers in the second year after the method change.