interest in applying CEA practices to urban agriculture (UA), including small- (e.g., in-home production or indoor gardens), medium- (e.g., community gardens), or large-scale commercial operations [e.g., rooftop greenhouses or warehouse-based indoor “plant
Celina Gómez, Christopher J. Currey, Ryan W. Dickson, Hye-Ji Kim, Ricardo Hernández, Nadia C. Sabeh, Rosa E. Raudales, Robin G. Brumfield, Angela Laury-Shaw, Adam K. Wilke, Roberto G. Lopez, and Stephanie E. Burnett
A-Young Lee, Seon-Ok Kim, and Sin-Ae Park
In South Korea, urban agriculture is defined as the cultivation of crops and ornamental plants, and the cultivation of insects and animals using various living spaces in urban areas ( Korea Ministry of Government Legislation, 2017 ). In the United
Kent D. Kobayashi, Theodore J.K. Radovich, and Brooke E. Moreno
agriculture, urban agriculture, forest gardening, landscape ecology, green roofs, vertical farming, and space farming ( Table 2 ). Where appropriate, organic farming principles are briefly covered under the various topics. Table 2. Lecture and laboratory
Angela Y.Y. Kong, Cynthia Rosenzweig, and Joshua Arky
accessible for urban agriculture as cities and countries recognize the impact of diverting organic waste from landfills on greenhouse gas emissions ( Materials Management & Product Stewardship Workgroup–West Coast Climate and Materials Management Forum, 2011
Roland Ebel, Esmaeil Fallahi, John L. Griffis Jr., Dilip Nandwani, Donielle Nolan, Ross H. Penhallegon, and Mary Rogers
horticulture is widely congruent with the terms urban agriculture or urban farming. Urban horticulture is both a site characterization and a production strategy. During the past decade, the idea has left the circles of producers and scholars and has become
Joshua R. Gerovac, Joshua K. Craver, Jennifer K. Boldt, and Roberto G. Lopez
Multilayer vertical production systems using sole-source (SS) lighting can be used for the production of microgreens; however, traditional SS lighting methods can consume large amounts of electrical energy. Light-emitting diodes (LEDs) offer many advantages over conventional light sources, including high photoelectric conversion efficiencies, narrowband spectral light quality (LQ), low thermal output, and adjustable light intensities (LIs). The objective of this study was to quantify the effects of SS LEDs of different light qualities and intensities on growth, morphology, and nutrient content of Brassica microgreens. Purple kohlrabi (Brassica oleracea L. var. gongylodes L.), mizuna (Brassica rapa L. var. japonica), and mustard [Brassica juncea (L.) Czern. ‘Garnet Giant’] were grown in hydroponic tray systems placed on multilayer shelves in a walk-in growth chamber. A daily light integral (DLI) of 6, 12, or 18 mol·m−2·d−1 was achieved from commercially available SS LED arrays with light ratios (%) of red:green:blue 74:18:8 (R74:G18:B8), red:blue 87:13 (R87:B13), or red:far-red:blue 84:7:9 (R84:FR7:B9) with a total photon flux (TPF) from 400 to 800 nm of 105, 210, or 315 µmol·m−2·s−1 for 16 hours. Regardless of LQ, as the LI increased from 105 to 315 µmol·m−2·s−1, hypocotyl length (HL) decreased and percent dry weight (DW) increased for kohlrabi, mizuna, and mustard microgreens. With increasing LI, leaf area (LA) of kohlrabi generally decreased and relative chlorophyll content (RCC) increased. In addition, nutrient content increased under low LIs regardless of LQ. The results from this study can help growers to select LIs and LQs from commercially available SS LEDs to achieve preferred growth characteristics of Brassica microgreens.
Rachel Leisso, Bridgid Jarrett, Katrina Mendrey, and Zachariah Miller
Codling moth (Cydia pomonella) is a major insect pest of apple (Malus domestica). If unmanaged, then codling moth can infest nearly all apples in an orchard, where the flesh-tunneling larva leave frass-laden tracks in the fruit. Insecticide-based management requires accurate application timing (typically based on adult moth and/or degree-day monitoring) and multiple spray applications. Both the season-long commitment to codling moth monitoring and management and limited familiarity with insecticides, application tools, and proper application procedures can prevent a small-scale or backyard grower from effectively limiting fruit damage. In addition, an increasing segment of growers is interested in nonchemical alternatives. Bagging fruitlets early in the season could be a simple and effective method of codling moth management for this subset of growers. At our research orchard in Corvallis, MT, we tested a method combining fruit thinning and bagging using plastic bags the first season and nylon bags the second season. Plastic bags reduced the incidence of codling moth damage to fruit from 34% to 10%, but european earwig (Forficula auricularia) frass, which was found in more than 50% of plastic-bagged apples, made harvesting the fruit unappealing. We tested nylon fruit bags during the second year of the study. These bags did not significantly reduce the incidence of codling moth. Both the soluble solids content and titratable acidity were higher in unbagged fruit during the second year of the study, whereas color measurements indicated bagged fruit were greener on the shaded side of the fruit. Failure of the nylon bags may have been attributable to eggs laid before bagging, eggs laid or larva burrowing through bagging, or improper bag application methods. Further research could assess whole-tree bags, the addition of rubber bands or twist ties when applying nylon bags, pretreatment of fruit with horticulture oil, and/or dipping nylon bags in kaolin clay before application; however, these steps add time and increase costs, which may discourage the small-scale fruit grower. Overall, results indicate that fruit bagging holds promise for codling moth management; however, further work is needed to optimize the methodology.
Caitlin E. Splawski, Emilie E. Regnier, S. Kent Harrison, Mark A. Bennett, and James D. Metzger
Field studies were conducted in 2011 and 2012 to compare mulch treatments of shredded newspaper, a combination of shredded newspaper plus turfgrass clippings (NP + grass), hardwood bark chips, black polyethylene plastic, and bare soil on weeds, insects, soil moisture, and soil temperature in pumpkins. Newspaper mulch or black plastic reduced total weed biomass ≥90%, and woodchip or NP + grass mulch each reduced total weed biomass 78% compared with bare soil under high rainfall conditions in 2011. In 2012, under low rainfall, all mulches reduced weed biomass 97% or more compared with bare soil. In both years, all mulches resulted in higher squash bug infestations than bare soil. The woodchip, newspaper, and NP + grass mulches retained higher soil moistures than bare soil or black plastic over the course of each growing season, and the woodchip and NP + grass mulches caused greatest fluctuations in soil temperature. Pumpkin yields were abnormally low in 2011 and did not differ among treatments. In 2012, all mulches produced greater total marketable pumpkin fruit weights compared with bare soil, but only black plastic, newspaper, and NP + grass mulches resulted in greater total numbers of marketable pumpkins. Overall results indicate that shredded newspaper or NP + grass mulches may be useful for organic and/or small-scale urban crop producers as sustainable alternatives to black plastic mulch; however, their weed suppression efficacy may require higher application rates with increasing moisture conditions, and they may require greater squash bug control measures than under bare soil conditions.
Elisa Solis-Toapanta, Andrei Kirilenko, and Celina Gómez
Social media platforms such as Reddit, centered on user-generated, anonymous discussions, can facilitate the exchange of information and resources across niche online communities known as “subreddits.” Using data mining tools and content analysis methods, our objectives were to identify recurring questions and characterize comment (“response”) accuracy from four subreddits focused on hydroponic indoor gardening (r/hydro, r/Hydroponics, r/UrbanFarming, and r/Aerogarden). A total of 1617 original posts (OPs) were classified into one of ten topics and 4891 primary responses were analyzed for accuracy. The three topics with the most OPs (production systems, plant lighting, and root-zone environment), which accounted for 50% of the total OPs, were subcategorized and inductively analyzed. Most posts in the analyzed subreddits related to confusion regarding the design and implementation of appropriate hydroponic production systems. In addition, misinformation about plant lighting is a major part of discussions about growing plants indoors. There are also knowledge gaps regarding nutrient solution management, particularly about fertilizer formulation, pH balance, and on the impact that solution temperature has on plant growth and development. In general, there were no differences among response accuracy for all topics included in our analysis. However, regardless of topic, responses for most OPs had less than 50% accuracy, which demonstrates that misinformation can be disseminated in social media platforms such as Reddit. As suggested by the results of this study, targeted, open access research and outreach efforts offer an opportunity to address knowledge gaps among consumers interested in indoor gardening.
Elisa Solis-Toapanta, Paul R. Fisher, and Celina Gómez
Interest in hydroponic home gardening has increased in recent years. However, research is lacking on minimum inputs required to consistently produce fresh produce using small-scale hydroponic systems for noncommercial purposes. Our objectives were to 1) evaluate the effect of biweekly nutrient solution replacements (W) vs. biweekly fertilizer addition without a nutrient solution replacement (W/O) on final growth, yield, and nutrient uptake of hydroponic tomato (Solanum lycopersicum) plants grown in a greenhouse, and 2) characterize growth over time in a greenhouse or an indoor environment using W. For each environment, ‘Bush Goliath’ tomato plants were grown for 12 weeks in 6.5-gal hydroponic systems. The experiment was replicated twice over time. In the greenhouse, plants were exposed to the following day/night temperature, relative humidity (RH), and daily light integral (DLI) in 2018 (mean ± SD): 31 ± 6/22 ± 2 °C, 67% ± 8%, and 32.4 ± 7 mol·m‒2·d‒1; and in 2019: 28 ± 6/22 ± 3 °C, 68% ± 5%, and 27.7 ± 6 mol·m‒2·d‒1. For both experimental runs indoors, the day/night temperature, RH, and DLI were 21 ± 2 °C, 60% ± 4%, and 20 ± 2 mol·m‒2·d‒1 provided by broadband white light-emitting diode lamps. The W/O treatment resulted in a higher-than-desired electrical conductivity (EC) and total nutrient concentration by the end of the experiment. In addition, compared with the W treatment, W/O resulted in less leaf area, more shoot growth, less water uptake, and similar fruit number—but increased blossom-end-rot incidence, delayed fruit ripening, and lower fruit fresh weight. Nonetheless, the final concentration of all nutrients was almost completely depleted at week 12 under W, suggesting that the applied fertilizer concentration could be increased as fruiting occurs. Surprisingly, shoot biomass, leaf area, and leaf number followed a linear trend over time in both environments. Nonetheless, given the higher DLI and temperature, greenhouse-grown plants produced 4 to 5 kg more of fruit than those grown indoors, but fruit from plants grown indoors were unaffected by blossom-end-rot. Our findings indicate that recommendations for nutrient solution management strategies should consider specific crop needs, growing environments, and production goals by home gardeners.