Yield and Phytochemical Quality of Saffron Stigmas and Tepals Are Influenced by Corm Size and Production Environment in Northern New Mexico

Saffron is the world’s most valuable spice, prized for the unique flavor of its dried stigmas and the medicinal properties of its bioactive compounds. Domestic production of saffron in the United States remains limited despite increasing market demand and growing concerns over global supply chain disruptions, highlighting the need for identification of new production zones. In addition to the stigmas used to produce saffron spice, saffron tepals contain high concentrations of phenolics and exhibit strong antioxidant capacity. This study evaluated the suitability of northern New Mexico as a saffron production region and determined the effects of production environment and corm size on yield, total phenolic content (TPC), and ferric reducing antioxidant power (FRAP) of saffron stigmas and tepals. Saffron was grown in two production environments [open field (OF) and high tunnel (HT)] using three corm sizes [small (8–9 cm), medium (9–10 cm), and large (>10 cm)]. Dry stigma yield ranged from 1.4 to 4.5 kg·ha −1 dry weight, demonstrating that saffron can be successfully integrated into northern New Mexico farming systems as a high-value, low-input crop. TPC of stigmas and tepals ranged from 21.7 to 25.5 in stigmas and from 17.0 to 21.8 mg gallic acid equivalents (GAE) per gram in tepals, whereas FRAP ranged from 57.1 to 64.3 mg Trolox equivalents (TE) per gram and 26.3 to 31.9 mg TE/g in stigmas and tepals, respectively. Although production environment did not significantly affect stigma yield, both TPC and FRAP were 5% to 7% higher under OF production than in HT. Corm size significantly affected saffron yield and phytochemical quality. Large corms produced 54% and 23% greater dry stigma yield than small and medium corms, respectively, while increasing TPC by 2% to 6% and FRAP by 4% to 8%. These findings indicate that saffron can be successfully grown in northern New Mexico and that larger mother corms may improve both yield and phytochemical quality. Further research is needed to evaluate its long-term agronomic and economic viability.