Herbal products with an estimated global market of $10.7 Billion in 2023 continue to gain popularity as health supplements. A lack of adapted, high yielding varieties, and production technology are major limiting factors for commercial production of ready-market herbs. The objective of this research was to address these limitations, and in the process develop production practices for a high-value multiple use herb, Virginia mountain mint (Pycnanthemum virginianum) that can be easily grown in North Alabama, USA. Mountain mint is used in the medicinal and confectionery industries and could serve as an alternative to pepper mint. Four Virginia mountain mint varieties were evaluated for growth and essential oil content and composition using replicated field trials. The greenhouse-grown plants of the four varieties, (M1, M2, M3 and M4) were transplanted onto raised beds, covered with plastic mulch with drip irrigation tubing underneath in mid-May, and grown using organic production methods. The crops were harvested at 135 (H1), 155 (H2), and 170 (H3) days after planting (DAP) to determine growth, biomass, essential oil yield, and composition. The chemical compositions of essential oils were determined by gas chromatography-mass spectrometry (GC-MS) and gas chromatography–flame ionization detection (GC-FID). Two of the four mountain mint varieties with high biomass showed consistently high yield potential in North Alabama. They were rich in isomenthone concentrations, which increased dramatically from 20% to 69% as the season advanced, whereas pulegone and thymol tended to decrease. The essential oil components varied with varieties and with time. The two mountain varieties with desirable essential oil composition offer potential for production as high-value medicinal crop in North Alabama.
Specialty tea made from Camellia sinensis has gained popularity in the U.S. This sensory evaluation study was conducted to understand consumer acceptance and preferences for cold brewed U.S.-grown black tea. Six cold brew black tea samples were evaluated: five from U.S. growers (‘Big Easy’, ‘Black Magnolia’, ‘Hawaii Black Assamica’, ‘Hawaii Black Sinensis’, ‘Summer Black’) and one from Taiwan (‘Sun
Saffron, scientifically recognized as Crocus sativus, is a perennial plant celebrated for its vibrant red stigmas. This crop has been cultivated for more than 3,000 years, originating in ancient Persia. The climate of northern New Mexico appears conducive to saffron cultivation, suggesting its viability for small-scale farmers in the area. The initiative seeks to introduce saffron as a low-input, high-value crop suited for New Mexico's agricultural landscape. Research performed during 2023 and 2024 indicates that saffron can flourish in this region's climate, demonstrating promising stigma yields in the initial years. This research program assesses how corm size, planting timing, and irrigation levels impact saffron flower and stigma production within both hoop house and open field systems at the Certified Organic Farm of the Alcalde Sustainable Agriculture Science Center of New Mexico State University. Results reveal that larger corms yield significantly more stigmas compared to smaller ones; specifically, corms larger than 10 produced over 5 kg/ha of dry stigma yield in their first and second years. However, there was no significant difference noted between yields from high tunnel versus open field systems. Additionally, planting saffron corms earlier—around mid-August—instead of later dates like late August or mid-September resulted in enhanced stigma production (approximately 6 kg/ha). Conversely, variations in irrigation treatments did not significantly affect first-year stigma yield. Measurements of total phenolic content (TPC) and antioxidant activity demonstrated that both saffron stigmas and flowers lacking stigmas are valuable sources of phenolic compounds, with saffron stigmas exhibiting higher TPC than those flowers without stigmas. In conclusion, the findings from this research indicate that saffron can be successfully cultivated even in an open field system in northern New Mexico. Employing larger corms and opting for mid-August planting could lead to increased yields in the first year.
Soil salinity, often governed by complex ion mixtures, remains a significant challenge in agriculture. However, most salinity research focuses on simple salts like sodium chloride. To develop effective salinity mitigation techniques in real-world applications, it is crucial to understand the impact of complex salts on plant physiology. Endophytic mycorrhizal fungi offer a promising method to mitigate salinity stress in plants by colonizing the plant roots. Shiso (Perilla frutescens L.) is a valuable culinary herb with rich source of phytochemicals. This study investigated the interaction of mycorrhizal inoculation and complex salinity on two shiso cultivars, Asia IP and Britton, and impacts on plant growth and phytochemical composition. Two replicated trials were designed to assess the effect of three different salinity rates (1, 3, 5 dS/m and control DI water) on both inoculated and non-inoculated shiso cultivars. Plant parameters like plant height, shoot and root fresh and dry weight along with root length were measured. Phytochemicals, total phenolic content (TPC) and total flavonoid content (TFC), proline and chlorophyll were also measured. Results showed that complex salts significantly reduced the overall fresh and dry biomass in both cultivars across both trials. The interaction of salinity and cultivar affected TPC of shiso in the first trial whereas only cultivar affected TPC in the second trial. No effect of salinity was seen in the second trial. However, TFC was significantly reduced by salinity in the second trial and no effect of salinity was seen in the first trial. Greater TFC was found in the Britton cultivar across both experiments. Proline content was increased steadily with increases in salinity rate across both trials. Greater proline content was found in the Britton cultivar in both trials. Chlorophyll content of shiso was unaffected by cultivar and salinity rates. The effect of salinity was cultivar dependent on growth and phytochemicals which was found in this experiment where Britton cultivar was more severely affected by salinity. These results show that complex salt negatively impacts the growth of shiso with no beneficial impact in increasing phytochemicals. Additionally, mycorrhizal inoculation was unable to mitigate the negative effect of salinity in shiso cultivars. Selection of effective mycorrhizal products is necessary in order to see their beneficial effects, so more screening should be done in the future. Further in-depth research is also required to fully understand the relationship of complex salts and mycorrhizal inoculation in shiso.
Many hydroponic fresh-cut herb producers in the United States utilize water sources with a high pH. Nutrient solutions with a high pH can prevent essential nutrients from being accessible for plant growth and development, especially micronutrients. The objectives of our research were to better understand how the growth of culinary herbs is impacted by supra-optimal pH and determine if supplemental micronutrients are an effective mitigation technique. Two week old seedlings of basil (Ocimum basilicum ‘Nufar’), and three week old seedlings of dill (Anethum graveolens ‘Hera’), parsley (Petroselinum crispum ‘Giant of Italy’), and sage (Salvia officinalis), grown in phenolic foam cubes were transplanted into one of six deep-flow technique (DFT) systems in a greenhouse. Herbs were grown in nutrient solutions with a pH of 6.0. 7.0, and 8.0, and either with a 1X or 2x micronutrient concentration. The DFT systems contained nutrient solutions made with tempered municipal water supplemented with a complete water-soluble fertilizer (16N-2.2P-14.3K) to create a target electrical conductivity of 2.0 dS·m–1, plus a supplemental micronutrient blend provided from the manufacturer to increase micronutrient concentrations for 2x micronutrient treatments. The nutrient solution pH was maintained through a dosing system using 2% H2SO4 v/v or 2% KOH w/v as the acid and alkali, respectively. One-third (by vol.) of the nutrient solution was renewed with freshly mixed fertilizer each week of production. Target greenhouse environmental conditions consisted of day and night air temperatures of 22 °C and 18 °C respectively, and a daily light integral of 12 mol∙m–2∙d–1. The experiment was replicated four times over time, and data was collected four weeks after herbs were transplanted into DFT systems. There were no significant interactions between micronutrients and pH. While high pH decreased dill, parsley, and sage shoot height, width, and fresh mass, providing supplemental micronutrients in the nutrient solution did not mitigate growth suppression induced by high pH. Additionally, all species had significantly shorter roots at a high pH of 8.0 compared to a moderate pH of 6.0, without a subsequent reduction in root mass. This study indicates nutrient solutions with a high pH can severely limit the growth of culinary herbs. While providing supplemental micronutrients does not alleviate the impact of high pH, producers can rely on other methods, such as acid injection, to lower the nutrient solution pH to maximize nutrient uptake.
Today, fresh herbs can be sourced as live container-grown plants year-round in the produce section of most retailers. Commercial fertilizers are selected based on several factors, including the ratio of ammonium- and nitrate-nitrogen and phosphorous concentration. The objective of this research was to quantify the effects of increasing phosphorus concentrations alongside different ratios of nitrate and ammoniacal nitrogen concentrations in commercial water-soluble fertilizers on the post-production performance of containerized culinary herbs. Seedlings of sweet basil (Ocimum basilicum ‘Genovese’) were transplanted into 11.4 cm-diameter containers filled with soilless substrate compromised of peat moss and coarse perlite. Upon transplant and throughout the experiment, seedlings were irrigated with commercially available water-soluble fertilizer (WSF) solutions variying in potential acidity (PA) or potential basicity (PB) and the ratio of nitrogen to phosphorous (N:P), including: 15N-0.9P-12.5K (PB 195 CCE/ton; 167N:10P); 15N-1.8P-16.6K (PB 77 CCE/ton; 83N:10P); 15N-2.2P-12.5K (PB 69 CCE/ton; 68N:10P); 15N-4.8P-14.1K (PA 58 CCE/ton; 15N-7P-24.1K (PA 122 CCE/ton; 21N:10P); and 20N-4.4P-16.6K (PA 401 CCE/ton; 45N:10P); 31N:10P). Plants were grown in two different phases: 1) in a greenhouse for 28 d at 22°/18° and 12 mol∙m–2∙d–1 to simulate a greenhouse production phase; and 2) in a growth chamber for 7 d at 20° ADT and 1 mol∙m–2∙d–1, to simulate a production and retail environment, respectively. After each phase, data was collected on half of the plants.. Plant height increased by 1.7 cm across treatments between the end of the greenhouse phase and the end retail phase. The relative growth rate of fresh mass accumulation decreased from 5.7 g∙d–1 during production to 1.2 g∙d–1 during the retail phase. Similarly, relative growth rate of dry mass accumulation decreased from 0.5 g∙d–1 during production to -0.2 g∙d–1 during the retail phase. The pH during the greenhouse phase was higher for basil fertilized with higher-nitrate formulations compared to those receiving fertilizers with more ammonium, but these differences were diminished during the retail phase. The results of this study indicate environment has a greater impact on plant growth and development than both the potential basicity or acidity and phosphorus content of fertilizer provided.
Lavender (Lavandula sp) is an important source of high-quality perfumes and has multiple medicinal properties, such as anti-anxiety, anti-depressant, and hypnotic properties. Due to its high market price and medicinal value, lavender essential oil was analyzed. There is a need for rapid, robust, easy, accurate, and cost-effective methodologies for quality control of essential oils from medicinal and aromatic plants. This research evaluated the ability of Fourier transform infrared (FTIR) spectroscopy techniques to identify the of lavender essential oil. Principal component analysis (PCA) was successfully used with 100% accuracy to differentiate lavender essential oil samples from three cultivars. The essential oils linalool and linalyl were identified. The results demonstrated that FTIR spectroscopy can be used as a reliable, robust, rapid, accurate, and low-cost analytical technique for quality assessment of Lavandula essential oil. This study aimed to develop a new and rapid spectroscopic method using chemical modeling techniques for the qualitative and quantitative identification of essential oils in three lavender essential oil species (Lavandula angustifolia, Lavandula intermedia, and Lavandula stoechas). Fifty-two principal component analysis (PCA) models were created, and the one with the best statistical results was evaluated. The best discrimination and quantitative analysis models were found to be those using standardized spectra. The results obtained demonstrated the possibility of successfully detecting the essential oils of three lavender species within a wide concentration range, without the use of any toxic chemicals or pretreatments. The results showed that FTIR models were able to accurately predict all constituents and identify essential oils in lavender. Lavender essential oil was extracted from lavender samples using the Soxhlet technique using 70% alcohol and compared using Fourier transform infrared (FTIR) spectroscopy. FTIR analysis of the pure essential oil extracted from three lavender species revealed distinct peaks for linalool and linalyl, the two main chemical components.
This presentation is hosted by the Collegiate Activities Committee and undergraduates are encouraged to attend!
Specialty teas made from the tender tips of Camellia sinensis have been enjoyed for centuries, and their cultivation in the U.S. is gaining growing interest. Join us at this Hort Theater presentation to discover the exciting world of U.S.-grown specialty tea. Experience a tasting of select green and black teas from Hawaii, Louisiana, and Mississippi. Bring your curiosity and your questions about the health benefits, production, processing, and preparation of tea – we’ll entertain these topics with fun facts and our latest research insights.
Audience will take part in the discussion by doing a tea tasting of 4 or 5 different U.S.-grown teas. There will be new 2025 tea products from a local grower and growers from Mississippi, Oregon, and Hawaii. We will be offering these teas as cold-brew and hot-water brewed sample.
