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The use of paper or nylon bags (fruit bagging) to surround tree fruit during development provides protection from a variety of pest-disease complexes for peach without yield reduction and different-colored bags have the potential to improve fruit quality based on findings from other crops. An experiment was conducted in 2019 at two locations in central Florida on peach [Prunus persica (L.) Batch] ‘TropicBeauty’ and ‘UFSun’ to analyze the impact of a commercially available white paper fruit bag combined with a photoselective insert. The insert reduced the amount of light outside the spectrum range of interest for blue (400–500 nm), green (500–600 nm), or red (>600 nm) wavebands, or decreased fluence rate with a neutral density black (>725 nm) insert. Relative to ambient, temperature inside all bagging treatments during the daytime hours was increased by 5.1 °C. During the same time, relative humidity was reduced by 10.1%, but calculations revealed that the water vapor pressure was elevated only for treatments that had a plastic colored (blue, green, or red) insert. An orthogonal contrast revealed that the elevated water vapor around the fruit in a colored bag increased the concentration of chlorophyll at harvest but had no effect on other quality parameters. Compared with unbagged fruit, red-bagged fruit were 1.8 times firmer and green-bagged fruit and had a lower peel chroma. White-bagged (without photoselective insert) fruit had similar nutrient concentrations for the peel, flesh, and pit when compared with unbagged fruit. When bags remained on the fruit until harvest, anthocyanin concentration in unbagged fruit peel was double the amount in white bags and 6-fold more than the bags with color inserts. Different-colored bagging treatments did not influence insect attraction or fruit quality parameters, such as fruit size, diameter, difference of absorbance (DA) index, total soluble solids (TSS), titratable acidity (TA), pH, peel lightness, peel hue, flesh lightness, flesh hue, or flesh chroma. Relative to full sun, the colored bag treatments allowed between 3.7% (black) and 17.4% (red) of the photosynthetically active radiation (PAR). Additional research is needed to determine if an increase in fluence rate at specific spectral wavelengths can affect the quality for peach grown in bags in the field.

Bell pepper (Capsicum annuum L.) production under high tunnels requires appropriate plant density and growth habit to ensure efficient use of space. This study assessed the effects of in-row spacin...

Fruit bagging is an acceptable cultural practice for organic production that provides a physical barrier to protect fruit. It can reduce pest and pathogen injury for a variety of fruit crops, but quality attributes have been inconsistent for peach [Prunus persica (L.) Batsch] and other bagged fruit. A 2-year experiment on a U.S. Department of Agriculture (USDA) organic-certified peach orchard in central Florida was conducted to analyze the effects of a commercially available paper bag designed for fruit protection and cardinal quadrant (north, south, east, and west sides) of the tree canopy on low-chill peach ‘TropicBeauty’ fruit quality. Protective bags appeared to delay fruit maturity. Flesh firmness and chlorophyll concentration of bagged fruit were 31% and 27% greater than unbagged fruit, respectively. Bagged fruit were protected as demonstrated with a reduction in mechanical injury by 95%, fruit fly injury by 450%, and scab-like lesions by 810%. Bagging reduced fruit brown rot (Monilinia fructicola) at harvest and 7 days after harvest; unbagged fruit were 2 and 3.5 times more likely to have rot at harvest and 7 days after harvest, respectively. Fruit bags did not affect yield, fruit size, total soluble solids, titratable acidity, pH, peel lightness, peel hue angle, or flesh color. Overall, canopy cardinal quadrant location had minimal effect on fruit quality or fruit injury. These results demonstrate that bagging peach fruit protects against various pests and diseases but has minimal effects on fruit quality. Broad adoption of this technology is highly dependent on available labor, market demands, and profitability but may be suitable for producers using direct-to-consumer market channels.

Florida’s K–12 schools provide a potential opportunity to increase market channel options for small- and mid-sized diversified farms, but processing, storage, and distribution resources are extremely limited for smaller producers. This 9-page document serves as a model and case study with steps for producers and other stakeholders to conduct a feasibility study before forming a cooperative to sell local fruits and vegetables to schools and other institutional food-service outlets. Written by Jonathan Adam Watson, Danielle D. Treadwell, Catherine Campbell, and Ray Bucklin, and published by the UF/IFAS Department of Agricultural and Biological Engineering, March 2021.

Growing your own Florida vegetable garden can be a rewarding experience with a little planning. This 5-page publication of the UF/IFAS Horticultural Sciences Department presents an overview of proper seed selection and planting. It also provides best management practices, as well as relevant terms and methods, for seeding vegetables in home and community gardens. Written by Danielle Treadwell, David Outerbridge, Tabitha Petri, and James M. Stephens.https://edis.ifas.ufl.edu/vh026 Original Publication: Stephens, James M. (1994) Seeding the Garden. Fact Sheet HS-506 (March 1994). Florida Cooperative Extension Service, Gainesville FL.

Organic farming is one of the fastest-growing segments of the agricultural industry in the United States and in Florida. Conservation tillage is often employed to reduce soil erosion, improve physical and biological properties of soil, and increase water use efficiency. This 5-page article aims to provide recommendations to row crop farmers who wish to implement conservation tillage practices during their transition to a certified organic system. Written by D. L. Wright, J. Moyer, D. Treadwell, I. M. Small, and S. George, and published by the UF/IFAS Agronomy Department, revised November 2020.

There is a growing market in the United States and globally for fresh fruits and vegetables with reported health-enhancing properties. This includes blueberries, which are high in antioxidants and have been reported to improve heart health and contain anticancer properties. Fresh-market blueberry sales (conventional and organic) increased by 27% between 2013 and 2017, and that trend is expected to continue. In addition, there is an increasing level of consumer interest in organically grown produce (for environmental conservation, taste, and other perceived benefits), for which some consumers are willing to pay a premium over the price for a conventionally produced crop. This new 8-page publication of the UF/IFAS Horticultural Sciences Department discusses various aspects of organic blueberry production in Florida and is intended for use by those currently using or interested in pursuing organic production. Written by Douglas A. Phillips, Peter J. Dittmar, Philip F. Harmon, Oscar E. Liburd, Danielle D. Treadwell, and Jeffrey G. Williamson.https://edis.ifas.ufl.edu/hs1400

El manejo de nutrientes es la implementación de prácticas que permitan obtener un rendimiento óptimo de cultivo y al mismo tiempo minimizar el impacto ambiental. El objetivo de esta publicación es proporcionar principios y prácticas para el manejo de nutrientes en la producción de hortalizas. Este completo artículo contiene recomendaciones de fertilidad para los principales cultivos de Florida, instrucciones para el cálculo de fertilizantes, una guía para detectar deficiencias de nutrientes y más. This is a minor revision adding Tatiana Sanchez as author.

El desarrollo y planificación de un huerto en el hogar, es una actividad agrícola que puede realizarse durante todo el año en Florida. Puede ofrecer muchos beneficios para la salud física y emocional. Los huertos nos proveen alternativas para realizar ejercicios, disfrute del huerto, producción de vegetales frescos y nutritivos, ahorro económico y muchos otros. Esta guía proporciona recomendaciones para hacer un huerto en su residencia y comunidad, e incluye las fechas de siembra, la selección de variedades para la planificación de cultivos, el manejo de agua, nutrientes, plagas y la cosecha. Vegetable gardening is a year-round activity in Florida that provides opportunities for exercise, mental therapy, enjoyment, nutritious fresh vegetables, economic savings, and many other benefits. This guide provides vegetable gardening recommendations for home and community gardeners, including planting dates, variety selection, water and nutrient management, pest management, and harvesting. This is a translation of SP103/VH021, Florida Vegetable Gardening Guide. Written by Sydney Park Brown, Danielle Treadwell, J. M. Stephens, and Susan Webb; translated by Francisco Rivera; and published by the UF/IFAS Horticultural Sciences Department.https://edis.ifas.ufl.edu/hs1383

Field production of organic crops, including herbs, in south Florida is a challenging task due to the subtropical climate and high number of pest and disease pressures. Thus, greenhouse production of organic herbs may provide an alernate to field production. However, there is little published information on selecting media and fertilizers for organic herb production in greenhouses in this climate. Greenhouse trials were conducted during the 2005 and 2006 growing season at the UF/IFAS Tropical Research and Education Center (TREC) in Homestead, Florida. The objectives of the project were to 1) compare several commercially available organic fertilizers for organic greenhouse production of container herbs and 2) compare two commercially available potting media for organic greenhouse production of container herbs. The two potting media (Fafard and Agro-Soils) did not result in significant differences in measured plant mass production, plant tissue nutrients, or leachate chemistry. However, some differences in plant production for basil and dill were identified among the different fertilizer treatments (Natural Safe, Perdue, Fertrell, and Control). These differ- ences were most notable for visual quality, fresh weight, and dry weight measurements. Evaluation of these parameters for basil and dill suggested that the two best fertilizers were Perdue and Fertrell. However, the differences in cost of each fertilizer and the study results suggest that Perdue is a more economic choice for organic herb production of basil and dill.

Organic and conventional production are common in horticulture crops and each system may exert a different influence on the soil ecosystem, particularly the nematode community. Crop nutrient rate is an important choice in both production systems. The objectives of this study were to assess the impacts of (i) organic and conventional production systems and (ii) nutrient rate in both systems on the nematode community in carrot production. To investigate these objectives, field studies in organic and conventional production – which included fumigation with 1,3-dichloropropene – were conducted in North-Central Florida. In both production systems, nutrient rate treatments were 168, 224, 280, 336, and 392 kg N/ha. Poultry litter was the nitrogen source in organic production whereas synthetic, inorganic fertilizer was used in conventional production. All nematode trophic groups were consistently more abundant in organic than conventional production. The nematode community was more diverse and had greater trophic structure in organic production. Greater rates of organic nutrients increased enrichment opportunists (bacterivores and fungivores), but inconsistently across years. Conventional production had similar results except that only moderate nutrient rates increased fungivore abundances. Extreme enrichment opportunists (Rhabditis spp.) drove bacterivore trends in organic production whereas moderate enrichment opportunists (Cephalobus spp.) drove trends in conventional production. Nutrient rates did not affect omnivore-predators, herbivores, nematode community diversity, or structure in either system. In summary, type of production system, organic or conventional, exerts a strong influence on the nematode community, but nutrient rate has less consistent effects in horticulture production.

Farm to school (F2S) programs aim to educate people about food and farming, to increase the availability of fresh, nutritious foods, and to improve health outcomes among children. Nationally, all states have school districts that self-identify as farm-to-school program participants. National and regional food procurement systems account for the majority of food purchased by National School Lunch Program participants, but school foodservice authorities (SFA) who purchase food from farmers often do so in the context of strengthening their farm-to-school program (U.S. Department of Agriculture [USDA], n.d.-b). A greater number of local supply chain participants benefit when food is sourced in state (locally) rather than out-of-state because more money ends up in the pockets of local producers and distribu­tors. Local fruit and vegetable producers and SFAs interested in developing business partnerships for local procurement would benefit from recommen­dations on menu-appropriate fresh market prod­ucts, volume, and purchase prices. However, detailed data sets from SFAs are uncommon, limiting opportunities to advance procurement efforts. The objective for this project was to begin developing local procurement recommendations for other Florida school districts based on the purchasing history and experiences of the Sarasota County School District (SCSD). In 2014, Sarasota County, Florida, received a USDA F2S implementation grant, affording it the opportunity to develop its local procurement efforts. One deliverable from that project was a robust data set of school food purchases over a two-year period. With permission SCSD, we analyzed seasonal purchase variations and market prices of local and out-of-state fresh fruits, vege­tables, and egg purchases for 38 public schools in the SCSD. In this paper, we present an approach to estimate the potential of local procurement viability in the context of an emerging districtwide F2S program and recommend system changes based on the success of procurement efforts in SCSD and surrounding school districts in Southwest Florida.

A field study was conducted in 2008 and 2009 in Citra, FL, to evaluate the effects of seeding rate and removal of apical dominance of sunn hemp (Crotalaria juncea L.) on weed suppression and seed production by sunn hemp. Three seeding rates of sunn hemp were used: a representative seed production rate of 11 kg·ha−1, an intermediate seeding rate of 28 kg·ha−1, and a cover crop seeding rate of 45 kg·ha−1. Cutting the main stem at 3, 4, or 5 weeks after planting to break apical dominance was compared with an uncut treatment. Cutting had no significant effect on shoot biomass, photosynthetically active radiation (PAR) penetrating the canopy, and nondestructive leaf area index (LAI). As a result, cutting also had no effect on weed density and biomass in 2008 and very little effect in 2009. Increase in seeding rate resulted in linear decrease in PAR and increase in LAI in both years. Seeding rate had a greater effect on suppression of weed biomass than on suppression of weed density. There was a linear decline in sunn hemp branching with increased seeding rate in 2009 and, averaged across years, flower number decreased linearly with increased seeding rate. Cutting to break apical dominance induced branching but had no effect on flower number. No seed pod production occurred and we postulate that the lack of seed production may be the result of the absence of effective pollinators in fall when short-day varieties of sunn hemp flower in Florida.

Weeds are a major contributor to yield loss and reduction in yield quality in an agricultural setting, competing with the crop for resources like light, water, and nutrients. This competition along with the cost of weed management strategies like tillage and herbicides, are responsible for the economic impact of weeds, which can reach into the billions. In addition to the damage caused by direct competition, weeds can also harm crop plants by acting as reservoirs for destructive plant pathogens, the insect vectors that move these pathogens from plant to plant, or both. The objective of this publication is to summarize previously published weed-pathogen associations to help growers scout and monitor pathogens in weeds near production areas.https://edis.ifas.ufl.edu/hs1335

Interest in producing specialty melons (Cucumis melo) is increasing in Florida, but information on yield performance, fruit quality, and disease resistance of specialty melon cultivars grown in Florida conditions is limited. In this study conducted at Citra, FL, during the 2011 Spring season, 10 specialty melon cultivars were evaluated, in both certified organic and conventionally managed fields, including: Creme de la Creme and San Juan ananas melon (C. melo var. reticulatus), Brilliant and Camposol canary melon (C. melo var. inodorus), Ginkaku and Sun Jewel asian melon (C. melo var. makuwa), Arava and Diplomat galia melon (C. melo var. reticulatus), and Honey Pearl and Honey Yellow honeydew melon (C. melo var. inodorus). ‘Athena’ cantaloupe (C. melo var. reticulatus) was included as a control. ‘Sun Jewel’, ‘Diplomat’, ‘Honey Yellow’, and ‘Honey Pearl’ were early maturing cultivars that were harvested 10 days earlier than ‘Athena’. ‘Athena’ had the highest marketable yield in the conventional field (10.7 kg/plant), but the yield of ‘Camposol’, ‘Ginkaku’, ‘Honey Yellow’, and ‘Honey Pearl’ did not differ significantly from ‘Athena’. Under organic production, ‘Camposol’ showed a significantly higher marketable yield (8.3 kg/plant) than ‘Athena’ (6.8 kg/plant). ‘Ginkaku’ produced the largest fruit number per plant in both organic (10 fruit/plant) and conventional fields (12 fruit/plant) with smaller fruit size compared with other melon cultivars. Overall, the specialty melon cultivars, except for asian melon, did not differ significantly from ‘Athena’ in terms of marketable fruit number per plant. ‘Sun Jewel’, ‘Diplomat’, and ‘San Juan’ showed relatively high percentages of cull fruit. ‘Honey Yellow’, ‘Honey Pearl’, and ‘Sun Jewel’ exhibited higher soluble solids concentration (SSC) than ‘Athena’ in both organic and conventional fields, while ‘Brilliant’, ‘San Juan’, and ‘Ginkaku’ also had higher SSC than ‘Athena’ under organic production. ‘Honey Yellow’, ‘Sun Jewel’, ‘Brilliant’, and ‘Camposol’ were less affected by powdery mildew (caused by Podosphaera xanthii) and downy mildew (caused by Pseudoperonospora cubensis) in the conventional field. ‘Honey Yellow’ and ‘Camposol’ also had significantly lower aboveground disease severity ratings in the organic field compared with ‘Athena’, although the root-knot nematode (RKN) (Meloidogyne sp.) gall rating was higher in ‘Honey Yellow’ than ‘Athena’.

eOrganic is the organic agriculture community of practice (CoP) and resource area for eXtension. eOrganic’s primary community of interest (CoI) is organic farmers and the agricultural professionals who support them. The 250 members of the eOrganic CoP include farmers, researchers, certifiers, and extension/other agricultural professionals. eOrganic’s mission is to build a diverse national CoP and use web technologies to synthesize existing information, emerging science, and practical knowledge into information resources and training materials for its CoI. eOrganic strategies to achieve that mission include collaborative publication, stakeholder engagement, community development, project management, evaluation, and fundraising. eOrganic’s public site currently offers 240 articles, 250 videos, 80 webinars and broadcasts, and 100 frequently asked questions (FAQs). eOrganic CoP members have answered more than 1000 “Ask an Expert” questions. eOrganic authors collaboratively develop articles in eOrganic’s collaborative workspace, which undergo review by two anonymous reviewers and National Organic Program (NOP) compliance review. eOrganic will offer online courses in 2012. eOrganic stakeholders evaluated eOrganic articles and videos in 2010 and overall they stated that they were relevant, science-based, and useful. Three quarters of webinar and broadcast participants said the webinar improved their understanding of the topic, and 83% said they would recommend the webinar to others. Sixty-nine percent of webinar survey respondents stated that they changed practices or provided others with information as the result of the webinar. eOrganic surveyed active CoP members in 2011. Members view eOrganic as important because it is the only national organic agriculture resource with direct ties to university research and they considered all of eOrganic’s core activities important. eOrganic is supported by small grants from eXtension and subawards in more than 20 U.S. Department of Agriculture (USDA), National Institute of Food and Agriculture (NIFA) research/extension projects. To enhance its financial sustainability, eOrganic will work to solidify its partnership with NIFA programs and diversify its funding sources to include course fees and underwriters.

Greenhouse experiments were conducted in 2005 and 2006 near Live Oak, FL, to develop fertilization programs for fresh-cut ‘Nufar’ basil (Ocimum basilicum) and spearmint (Mentha spicata) in troughs with soilless media using inputs compliant with the U.S. Department of Agriculture's National Organic Program (NOP). Four NOP-compliant fertilizer treatments were evaluated in comparison with a conventional control. Treatments and their analyses in nitrogen (N), phosphorus (P), and potassium (K) contents are as follows: conventional hydroponic nutrient solution [HNS (150 ppm N, 50 ppm P, and 200 ppm K)], granular poultry (GP) litter (4N–0.9P–2.5K), granular composite [GC (4N–0.9P–3.3K)], granular meal [GM (8N–2.2P–4.1K)], and GM plus a sidedress application of 5N–0.9P–1.7K fish emulsion (GM + FE). Electrical conductivity (EC) of the media, fresh petiole sap nitrate (NO3-N) and K concentrations, dried whole leaf NO3-N, P, and K concentrations, and yield and postharvest quality of harvested herbs were evaluated in response to the treatments. Basil yield was similar with HNS (340 g/plant) and GP (325 g/plant) in 2005 and greatest with HNS (417 g/plant) in 2006. Spearmint yield was similar with all treatments in 2005. In 2006, spearmint yields were similar with the HNS and GP yields (172 and 189 g/plant, respectively) and greater than the yields with the remaining treatments. In both years and crops, media EC values were generally greater with the GC than with the GP, GM, and GM + FE treatments but not in all cases and ranged from 1.77 to 0.55 dS·m−1 during the experiments. Furthermore, HNS media EC values were consistently equal to or lower than the GP media EC values except with EC measurements on 106 days after transplanting in both crops in 2005. Petiole NO3-N and K results were variable among crops and years, but provided valuable insight into the EC and yield data. We expected EC, petiole NO3-N, and petiole K to be consistently higher with HNS than with organic treatments, but they were not, indicating a reasonable synchrony of nutrient availability and crop demand among the organic treatments. The postharvest quality of both basil and spearmint was excellent with all treatments with few exceptions.

Aquaponics combines the hydroponic production of plants and the aquaculture production of fish into a sustainable agriculture system that uses natural biological cycles to supply nitrogen and minimizes the use of nonrenewable resources, thus providing economic benefits that can increase over time. Several production systems and media exist for producing hydroponic crops (bench bed, nutrient film technique, floating raft, rockwool, perlite, and pine bark). Critical management requirements (water quality maintenance and biofilter nitrification) for aquaculture need to be integrated with the hydroponics to successfully manage intensive aquaponic systems. These systems will be discussed with emphasis on improving sustainability through management and integration of the living components [plants and nitrifying bacteria (Nitrosomonas spp. and Nitrobacter spp.)] and the biofilter system. Sustainable opportunities include biological nitrogen production rates of 80 to 90 g·m−3 per day nitrate nitrogen from trickling biofilters and plant uptake of aquaculture wastewater. This uptake results in improved water and nutrient use efficiency and conservation. Challenges to sustainability center around balancing the aquaponic system environment for the optimum growth of three organisms, maximizing production outputs and minimizing effluent discharges to the environment.

Soil solarization is an important practice for small-acreage farmers and home gardeners and is used commercially in areas with high solar radiation and air temperature during the summer. In this technique, clear plastic films are used to increase soil temperature to manage soil-borne plant pests such as insects, diseases, nematodes, fungi, and weeds. Several different kinds of plastic films were evaluated in 2007 and 2008 for durability, weather tolerance, and weed suppression. Treatments were arranged in a randomized complete block design with five replications. In 2007, treatments were four clear plastic films including: ISO, VeriPack, Poly Pak, Bromostop®, and a white plastic control. In 2008, treatments were Polydak®, Poly Pak, Bromostop®, and white plastic. Films were evaluated for weed suppression based on the population density of weeds that emerged through breaks in the plastic, for durability in terms of number and size of breaks in the films, and for the total exposed soil area resulting from breaks. Purple nutsedge (Cyperus rotundus) was the major weed problem throughout both years. In both years, total exposed area was greater with white plastic and Bromostop® (81.5 ft2/bed) compared with other plastic films (2/bed). Due to their durability, Poly Pak, ISO, and VeriPack suppressed nutsedge more than Bromostop and white plastic. Although a number of very small (

Cucumbers are produced in integrated hydroponic and aquaculture systems (aquaponics). Aquaponics balances pH for plants, fish, and nitrifying bacteria. Nitrification prevents buildup of toxic waste ammonia by conversion to nitrate (NO3 −)- nitrogen (N). The pH for hydroponic cucumbers (5.5–6.0) and nitrification (7.5–9.0) requires reconciliation to improve systems integration. Cucumbers were grown at pH of 5.0, 6.0, 7.0, and 8.0 with additional foliar sprays at pH 7.0 and 8.0. Plant shoot dry weight, length, N, and phosphorus (P) content at 14 DAT were similar from pH 5.0 to 7.0, but reduced at pH 8.0. Nutrient solution and shoot dry matter Mn and Fe decreased as pH increased. Foliar sprays had no effect on cucumber fruit yield. Early yield was higher at pH 5.0 compared to pH 8.0 but total yield was unaffected by pH. Cucumbers in recirculating culture may be maintained at pH levels more optimum for nitrification (7.5–8.0) except during production for early season markets.

A 3-year field experiment was initiated in 2001 to evaluate different organic sweetpotato production systems that varied in cover crop management and tillage. Three organic systems: 1) compost and no cover crop with tillage (Org-NCC); 2) compost and a cover crop mixture of hairy vetch and rye incorporated before transplanting (Org-CCI); and 3) compost and the same cover crop mixture with reduced tillage (Org-RT) were compared with a conventionally managed system (Conv) with tillage and chemical controls. Yield of No. 1 sweetpotato roots and total yield were similar among management systems each year, except for a reduction in yield in Org-RT in 2002. The percentage of No. 1 grade roots was at least 17% and 23% higher in Org-CCI and Org-NCC than Org-RT in 2001 and 2002, respectively, and similar to Conv in 2001 and 2004. Organic and conventional N sources contributed to soil inorganic N reserves differently the 2 years this component was measured. In 2002, soil inorganic N reserves at 30 DAT were in the order: Org-CCI (90 kg·ha−1) > Org-NCC (67 kg·ha−1) > Org-RT (45 kg·ha−1), and Conv (55 kg·ha−1). No differences in soil inorganic N reserves were observed among systems in 2004. Sweetpotato N, P, and K tissue concentrations were different among systems only in 2004. That year, at 60 days after transplanting, tissue N, P, and K were greatest in Org-CCI. In 2001 and 2004, N (4.09% to 4.56%) and K (3.79% to 4.34%) were higher than sufficiency ranges for N (3.2% to 4.0%) and K (2.5% to 3.5%) defined by North Carolina Department of Agriculture and Consumer Services recommendations for all treatments. No tissue macronutrient or micronutrient concentrations were limiting during this experiment. Reduced rainfall during the 2002 sweetpotato growing season may have contributed to the low microbially mediated plant-available N from the organic fertilizer sources. Despite differences in the nutrient content of organic and conventional fertility amendments, organically managed systems receiving compost with or without incorporated hairy vetch and rye produced yields equal to the conventionally managed system.

A 3-yr field experiment was initiated in 2001 to evaluate weed suppression and sweetpotato productivity in three organic sweetpotato production systems. Organic systems were (1) compost and no cover crop with tillage (Org-NC), (2) compost and a cover crop mixture of hairy vetch and rye incorporated before transplanting (Org-CI), and (3) compost and the same cover crop mixture with reduced tillage (Org-RT). A conventional system with tillage and chemical controls (Conv) was included for comparison. Suppression of monocot and dicot weed density and biomass was similar between Org-NC and Org-CI each year, and were frequently similar to Conv. Org-RT was as effective as Org-NC in controlling dicot weed density and biomass each year, but did not suppress monocot weeds. At sweetpotato harvest, an increase in cover crop surface residue biomass in Org-RT was associated with a decrease in cumulative total weed density (R2= 0.43, P = 0.0001); however, the amount of that residue was insufficient to suppress late-emerging monocot weeds. Total sweetpotato yield in Org-RT was at least 45% lower than other systems in 2002 and was most likely due to an increase in monocot weed density and biomass concurrent with a decrease in sweetpotato vine biomass. Total sweetpotato yield was similar among all systems in 2001 and 2004; the exception was lowest yields obtained in the Org-RT system in 2002. Organically managed sweetpotato with or without an incorporated cover crop produced sweetpotato yields equal to conventionally managed systems despite difficulties controlling weeds that emerged later in the season.

Reconciling water quality parameters in sustainable aquaponic (integrated hydroponic and recirculating aquaculture) systems requires balancing nutrients and pH for the optimal growth of three organisms: the plant, the fish, and the nitrifying bacteria. Nitrifying bacteria convert fish waste into nitrate (NO3 −)-nitrogen (N) that may be used by the plants. Fish waste rarely supplies nutrients in adequate amounts for plants without supplementation. Increasing nitrification rate and efficiency would allow greater stocking density for fish and increased nutrient loads for plants. The objective of this research was to determine the nitrification rate response in a perlite trickling biofilter (root growth medium) exposed to hydroponic nutrient solution, varying NO3 −-N concentrations, and to pH levels optimum for plants (6.5) and nitrification (8.5). The experiment used recirculating tank batch culture and was based on typical startup characteristics for bringing biological filters up to full capacity ...

Consumer demand for fresh market organic produce combined with the increasing market share of ready-to-eat products indicates the potential for expansion of an organic culinary herb market. Barriers to organic herb greenhouse production are high as a result of lack of available technical information and the low number of producers experienced in this area. There is a critical need for information and technologies to improve the management of organic soil and fertilizer amendments to optimize crop yields and quality, manage production costs, and minimize the risk from groundwater nitrogen (N) contamination. Because of limited information specific to organic culinary herb production, literature on organic vegetable transplants and conventional basil (Ocimum basilicum) production was also considered in this review. Managing N for organic crops is problematic as a result of the challenge of synchronizing mineralization from organic fertilizer sources with crop N demand. A combination of materials, including locally formulated composts, supplemented with standardized commercially formulated fertilizer products is one method to ensure crops have access to mineral N throughout their development. In experimental greenhouse systems, local raw materials are frequently used as media amendments to satisfy partial or complete crop fertility requirements. This makes comparisons among experiments difficult as a result of the wide variety of raw materials used and the frequent interactions of fertilizer source and planting media on nutrient availability. Nitrogen mineralization rates are also influenced by additional factors such as the environmental conditions in the greenhouse and physical and chemical properties of the media and fertilizer. Despite the variability within and among experimental trials, yields and quality of organically grown crops are frequently similar to, and occasionally better than, conventionally grown crops.

A field study was conducted in 2008 and 2009 at the USDA, ARS, Plant Genetic Resources Conservation Unit in Griffin, GA, to investigate weed suppression by sunn hemp (Crotalaria juncea L). The objectives were to (1) evaluate the effects of apical meristem removal (AMR) at three dates [5, 6, and 7 wks after planting (WAP) on May 14, 2008 and May 21, 2009] and (2) assess the impact of seeding rates (11, 28, and 45 kg ha(-1)) on weed biomass reduction. Weed species were identified at 4, 8, and 12 wks after sunn hemp planting. Sunn hemp cutting date had no significant effect on weed suppression in 2008 but significant differences for grass weeds at 4, 8, and 12 WAP and for yellow nutsedge at 8 and 12 WAP did occur when compared to the control in 2009. In comparison to the sunn hemp-free control plot in 2009, all three seeding rates had reduced grass weed dry weights at 4, 8, and 12 WAP. The total mass of yellow nutsedge when grown with sunn hemp was reduced compared to the total mass of yellow nutsedge grown in the weedy check for all seeding rates at 8 and 12 WAP. Lower grass weed biomass was observed by 12 WAP for cutting dates and seeding rates during 2008 and 2009. Sunn hemp cutting date and seeding rate reduced branch numbers in both years. The reduction in sunn hemp seeding rates revealed a decrease in weed populations.

Florida’s climate allows homeowners to grow their own delicious vegetables nearly year-round. Basic vegetable gardening information, planting dates, reliable varieties, and much more can be found in the Florida Vegetable Gardening Guide, available from your county Extension office or online at http://edis.ifas.ufl.edu/vh021. This publication is meant to be a companion document to the Florida Vegetable Gardening Guide. It is intended for the home gardener who prefers to use natural and organic materials as well as methods that are compatible with the philosophy of organic gardening. Commercial organic producers should refer to Introduction to Organic Crop Production (http://edis.ifas.ufl.edu/cv118).

Organic agriculture is an industry sector that has been experiencing steady global growth in recent years. The United States is ranked first in organic food consumption, followed by Germany and France. In 2014, the estimated market value of organic foods in the U.S. was $42 billion; 43% of this total was attributed to produce (fruits and vegetables). Organic production systems in the U.S. must adhere to National Organic Program (NOP) standards that integrate cultural, biological, and mechanical practices. These standards promote the recycling of resources and ecological balance while conserving biodiversity. While the U.S. organic produce sector is steadily expanding, many questions related to price, safety, nutritional quality, and consumer preference remain. This paper will provide comparisons and insights in the following areas: (1) the economic contribution and impact of the organic produce market; (2) the U.S. National Organic Standards and requirements, as well as the certification process; (3) the nutritional quality and safety of organic produce; (4) consumer attitudes and preferences regarding organic produce; and (5) future research directions and developments for the organic produce industry.

HS1126, a 6-page illustrated fact sheet by Danielle D. Treadwell and Mike Alligood, summarizes the recommended cultural practices to help vegetable growers grow a successful summer cover crop and to optimize the amount of nitrogen that is returned to a vegetable crop. Includes references. Published by the UF Department of Horticultural Sciences, January 2008.

HS-1135, a 7-page illustrated fact-sheet by Danielle Treadwell and Pei-wen Huang, describes this “pseudocereal” commonly grown as a cover crop in the southeast, growth habits, environmental requirements, role as a nutrient catch crop, interactions with insects, potential for weed control and weed suppression, and economics. Includes references. Published by UF Department of Horticultural Sciences, February 2008.

HS-1113, a 4-page illustrated fact sheet by Robert C. Hochmuth, Danielle D. Treadwell, Eric H. Simonne, Linda B. Landrum, Wanda L. Laughlin, and Lei Lani Davis, describes the results of trials of using soilless culture and shade to extend the bell pepper growing season through the hottest part of the summer and into fall. Includes tables of trial data. Published by the UF Department of Horticultural Sciences, July 2007. HS-1113/HS368: Growing Bell Peppers in Soilless Culture under Open Shade Structures (ufl.edu)

HS-1102, a 20-page fact sheet by Alejandra Sierra, Eric Simonne, and Danielle Treadwell, explains 5 key principles and 3 key practices for nutrient management in vegetable production for Spanish-speaking audiences. Includes references, and several tables. Published by the UF Department of Horticultural Sciences, July 2007. HS1102/HS356: Principios y prácticas para el manejo de nutrientes en la produccion de hortalizas (ufl.edu)

ABE-373, a 6-page report by K. W. Migliaccio, T. Olczyk, Y. Qian, Y. Li, G. J. Hochmuth, R. C. Hochmuth, D. D. Treadwell, E. H. Simonne, L. S. Osborne, and R. K. Sprenkel, presents the results of trials conducted in 2005 and 2006 to compare organic fertilizers and potting media for greenhouse production of container herbs. Includes references. Published by the UF Department of Agricultural and Biological Engineering, May 2007. ABE 373/AE408: Organic Greenhouse Container Herb Production in South Florida: Fertilizer and Potting Media (ufl.edu)

The effect of living mulches (LM) on weed suppression, crop growth and yield, and soil hydraulic conductivity were evaluated in broccoli in North Central Florida at Citra and in North Florida at Live Oak, using organic production methods. `Florida 401' rye, `Wrens Abruzzi' rye, black oat, and annual ryegrass, were either mowed or left untreated and compared with weedy and weed-free controls. Cover crop biomass was highest with `Florida 401' at both locations, intermediate with black oat and `Wrens Abruzzi', and lowest with ryegrass. The greatest weed infestation occurred with the weedy control. In Citra, ryegrass decreased weed biomass by 21% compared with ≈45% by the other LM with no differences due to mowing. However, at Live Oak, mowed LM and the weedy control had similar amounts of weed biomass; whereas unmowed LM had 30% to 40% less weed biomass than the weedy control. At both locations, broccoli heights were greatest with the weed-free control, intermediate with the cover crops, and lowest with the weedy control. Total above-ground broccoli biomass and marketable weight of broccoli at Live Oak, and number of marketable heads at both locations, were unaffected by the LM. At Citra, total broccoli biomass with LM and the weedy control decreased in a similar manner, so that total broccoli biomass was highest with the weed-free control. Ryegrass and the weedy control suppressed marketable broccoli weight by 24%; however, greater decrease in marketable weight (39% to 43%) occurred with `Florida 401', `Wrens Abruzzi', and black oat. At both locations, mowing of LM had no effect on broccoli growth or yield. There was no difference in saturated hydraulic conductivity among treatments.

Row intercropping sweet corn (Zea mays L.) with a living mulch of buckwheat (Fagopyrum esculentum Moench) may reduce weed competition without reducing sweet corn yields. The objective of this experiment was to examine competition for nutrients, crop water use, and plant growth between weeds, buckwheat, and organically grown sweet corn, and examine the impact of buckwheat on weed densities and corn yields. In 1999, `Bodacious' (sehybrid) sweet corn was planted to 41,000 plants/ha stand and the following treatments were applied: 1) `Manor' buckwheat planted at 0 kg·ha–1, 56 kg·ha kg·ha–1, and 112 kg·ha–1, 2) buckwheat planted at three times: planting corn, at four-leaf corn and eight-leaf corn stage. A RCB design with four replications including a weedy/weed-free split was used. Above ground biomass of buckwheat was measured within a 1/2-m2 quadrat 8WAP and analyzed for C and N. Weed densities were taken within a 1/2-m2 quadrat 4WAP and 8WAP following each buckwheat planting. Buckwheat and corn tissue samples were analyzed for total nutrient content 8WAP. Soil samples were taken in corn and buckwheat interrows at emergence, 4 WAP, 8 WAP, and at harvest, and evaluated for inorganic nitrogen and soil moisture. Within rate treatments, yield was highest in weed and buckwheat-free (16.3 MT·ha–1) and lowest in weed-free 112 kg·ha–1 buckwheat (8.5 MT·ha–1). Within buckwheat timing treatments, yield was highest in 8 leaf (18.2 MT·ha–1) relative to at plant buckwheat. Weed densities were highest in no buckwheat (281 no/m2) and lowest in 56 kg·ha–1 buckwheat (28 no/m2) compared to the controls. These findings indicate buckwheat rate influences yield and weed density more than timing of buckwheat plant.