Virginia mountain mint (Pycnanthemum virginianum) is a peppermint-flavored aromatic herb of the Lamiaceae and is mainly used for culinary, medicinal, aromatic, and ornamental purposes. North Alabama’s climate is conducive to growing mint for essential oils used in culinary, confectionery, and medicinal purposes. There is, however, a need for varieties of P. virginianum that can be adapted and easily grown for production in North Alabama. Towards this end, four field-grown varieties with three harvesting times (M1H1, M1H2, M1H3; M2H1, M2H2, M2H3; M3H1, M3H2, M3H3, M4H1, M4H2, M4H3) were evaluated for relative differences in essential oil yield and composition. Thirty-day-old greenhouse-grown plants of the four varieties were transplanted on raised beds in the field at the Alabama A & M University Research Station in North Alabama. The plots were arranged in a randomized complete block with three replications. The study’s objective was to compare the four varieties for essential oil yield and their composition at three harvest times, 135, 155, and 170 days after planting (DAP). Essential oils were obtained by hydrodistillation with continuous extraction with dichloromethane using a Likens–Nickerson apparatus and analyzed by gas chromatographic techniques. At the first harvest, the essential oil yield of the four varieties showed that M1H1 had a yield of 1.15%, higher than M2H1, M3H1, and M4H1 with 0.91, 0.76, and 1.03%, respectively. The isomenthone concentrations increased dramatically through the season in M1 (M1H1, M1H2, M1H3) by 19.93, 54.7, and 69.31%, and M3 (M3H1, M3H2, M3H3) by 1.81, 48.02, and 65.83%, respectively. However, it increased only slightly in M2 and M4. The thymol concentration decreased slightly but not significantly in all four varieties; the thymol in M2 and M4 was very high compared with M1 and M3. The study showed that mountain mint offers potential for production in North Alabama. Two varieties, M1 and M3, merit further studies to determine yield stability, essential oil yield, composition, and cultivation development practices.

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Growing interest in curcumin from turmeric (Curcuma longa L.) for medical and health purposes has led to interest in turmeric cultivation in the United States. The warm growing season in Alabama is short relative to tropical environments where the plant is normally grown, and research on cultural practices is lacking. A split‐split‐plot experiment was performed in Alabama to assess the effects of shade (40% shade vs. no shade), establishment method (early establishment in greenhouse over heat vs. direct seeding), and variety on rhizome yield and curcumin content. Canonical discriminant analysis revealed distinctive trends based on varietal differences, establishment methods, and presence or absence of shade. Extending the growing season by early establishment in the greenhouse increased rhizome and curcumin yield, as well as curcumin concentration in lateral rhizomes. Shade increased plant height, leaf size, and fresh weight of rhizomes, but an apparent increase in rhizome dry weight was not significant. Shade decreased curcumin concentration and yield in mother rhizomes but had little effect on curcumin concentration in lateral rhizomes. An apparent increase in curcumin yield in lateral rhizomes with shade was not significant. Significant differences among varieties were observed for rhizome yield and curcumin concentration and yield. Cultivation of turmeric in Alabama is feasible by extending the growing season and selection of short‐season varieties high in curcumin.

Turmeric (Curcuma longa L.) is an important spice, particularly is Asian cuisine, and is also used in traditional herbal medicine. Curcuminoids are the main bioactive agents in turmeric, but turmeric essential oils also contain health benefits. Turmeric is a tropical crop and is cultivated in warm humid environments worldwide. The southeastern United States also possesses a warm humid climate with a growing demand for locally sourced herbs and spices. In this study, five different varieties of C. longa were cultivated in north Alabama, the rhizome essential oils obtained by hydrodistillation, and the essential oils were analyzed by gas chromatographic techniques. The major components in the essential oils were α-phellandrene (3.7–11.8%), 1,8-cineole (2.6–11.7%), α-zingiberene (0.8–12.5%), β-sesquiphellandrene (0.7–8.0%), ar-turmerone (6.8–32.5%), α-turmerone (13.6–31.5%), and β-turmerone (4.8–18.4%). The essential oil yields and chemical profiles of several of the varieties are comparable with those from tropical regions, suggesting that these should be considered for cultivation and commercialization in the southeastern United States.

Curcuma (turmeric) species are important culinary and medicinal plants, and the essential oils of Curcuma rhizomes have demonstrated promising pharmacological properties. The essential oils (EOs) of Curcuma species possess a wide variety of pharmacological properties, including anti-inflammatory, anticancerous, antiproliferative, hypocholesterolemic, antidiabetic, antirheumatic, hypotensive, antioxidant, antimicrobial, antiviral, antithrombotic, antityrosinase, and cyclooxygenase-1 (COX-1) inhibitory activities, among others have been attributed to the essential components of Curcuma species. Curcuma oils are also known to enhance immune function, promote blood circulation, accelerate toxin elimination, and stimulate digestion. C. longa (turmeric) and C. zedoaria (zedoary) are the most extensively studied species of Curcuma due to their high commercial value. There is some interest in expanding the cultivation of Curcuma species to regions in North America where the climate is favorable. The purpose of this work was to examine the rhizome essential oil compositions of four species of Curcuma (C. aromatica, C. caesia, C. longa, C. zanthorrhiza) that were obtained from Vietnam and cultivated in North Alabama. The rhizome essential oils were obtained by hydrodistillation and analyzed by gas chromatographic techniques. The essential oils of C. aromatica were dominated by curzerenone (14.7–18.6%), germacrone (10.7–14.7%), 1,8-cineole (5.2–11.7%), and an unidentified component (8.7–11.0%). The major components in C. longa rhizome oil were ar-turmerone (8.3–36.1%), α-turmerone (12.7–15.2%), β-turmerone (5.0–15.4%), α-zingiberene (4.6–13.9%), and β-sesquiphellandrene (4.6–10.0%). The essential oils of C. caesia and C. zanthorrhiza were rich in curzerenone, curdione, and germacrone. These adapted turmeric varieties in North Alabama have potential use for medical purposes and medicinal plant oil market demands in the U.S.