Patients undergoing hematopoietic cell transplantation (HCT) commonly experience high levels of distress and other symptoms during the acute inpatient period. Inhaled aromatherapy is a low-burden, patient-directed supportive care strategy that may be feasible to deliver during hospitalization. This randomized, parallel-group study will evaluate the feasibility and acceptability of an aromatherapy inhaler ("aromatherapy stick") during the early post-transplant inpatient period and will explore short-term changes in patient-reported outcomes.