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The ornamental horticulture industry has long been significant in its vast economic contributions to the US agricultural sector, with Florida ranking second in nursery and greenhouse plant sales. A small proportion of introduced plants eventually escape cultivation and become invasive, leaving fragile ecosystems at risk. In response, a series of propagation and production research studies have been conducted over the years to 1) evaluate the female sterility and landscape performance of cultivars and/or hybrids of ornamental invasives, and 2) develop reliable propagation systems of novel or underused natives having ornamental and ecological value. Attractive, fruitless selections of popular species such as butterfly bush (Buddleja sp.), heavenly bamboo (Nandina domestica), Mexican petunia (Ruellia simplex), lantana (Lantana strigocamara), trailing lantana (Lantana montevidensis), privet (Ligustrum sp.), maiden silvergrass (Miscanthus sp.), and fountain grass (Pennisetum sp.) have been identified as suitable non-native alternatives to the invasive or potentially invasive resident species (wild type). Simultaneously, researchers have taken a closer look at native plant alternatives that may offer similar aesthetic traits as invasive plants, while bringing added biodiversity and function for more ecologically friendly landscapes and gardens. As such, successful multisite trialing and/or propagation systems have been developed for a number of species native to Florida, such as squareflower (Paronychia erecta), coastalplain honeycombhead (Balduina angustifolia), wireweeds (Polygonella sp.), blue porterweed (Stachytarpheta jamaicensis), wild coffees (Psychotria sp.), sweet acacia (Vachellia farnesiana), and wild lime (Zanthoxylum fagara). With pronounced marketing and consumer education, it is hopeful that together sterile cultivars and native species will ultimately replace wild-type forms of commercially available ornamental invasives. This paper summarizes the current status of ornamental invasives in Florida and the role of native species and sterile non-native cultivars.

Passionfruits (Passiflora sp.) are widely grown throughout tropical regions of the world. Burgeoning new interest in this fruit in both its fresh and processed forms has led to an increase in planting outside of traditional growing zones. Passionfruit production has increased steadily in the United States and its territories since the 2002 US Department of Agriculture Census of Agriculture; however, little is known about how the industry functions across production areas. To assess passionfruit growers’ production practices and support their needs, we conducted a survey during 2021. That survey consisted of 45 questions pertaining to various aspects of passionfruit production, including horticultural practices, pest management, cultivars grown, and industry challenges and needs. The objectives of the survey were to identify where passionfruit is currently grown in the United States, what production practices are being used, and what problems are being encountered so that researchers and extension personnel could provide remedies in the future. Forty-four surveys were complete and allowed for data analyses. Florida had the most responses (21), followed by Puerto Rico (12), California (6), Hawaii, Louisiana, Mississippi, and the Virgin Islands. Most of the passionfruit production in the United States comprises purple passionfruit (Passiflora edulis f. edulis) or intraspecific red types at 68.2%. This value is driven by the high amounts of purple passionfruit and red passionfruit in Florida and other states. In contrast, nearly all farms in Puerto Rico grow yellow passionfruit (P. edulis f. flavicarpa) and fewer purple types. The main obstacle to obtaining optimum production was labor availability. Managing passionfruit, like many other specialty crops, is labor-intensive and includes many activities that require manual labor, such as weeding, training, pruning, pollination, and harvesting. Other obstacles that were noted were weather variability, vine decline, poor pollination, and availability of high-quality cultivars. Diseases, especially fungal diseases, are of particular concern to growers of passionfruit in the United States, although the identification of specific diseases was limited. Online delivery methods of information ranked high on the list of desired products. Online articles, such as those offered by extension services, were the most preferred, followed by webinars, which comprise a more recently developed method of information delivery. Overall, the survey provided baseline information to further develop initiatives to aid passionfruit production within the United States.

In 2011, Rutgers, The State University of New Jersey (New Brunswick, NJ, USA) and Akdeniz University (Antalya, Turkey) conducted a survey to identify needs, interests, and capacities of Turkish women farmers. We interviewed extension educators and female farmers in three villages and used the results to develop a pilot, 28-hour course to train 40 small-scale citrus (Citrus sp.) and greenhouse producers from Kumluca, Turkey. Training included computer literacy, citrus and greenhouse production, and business management. The municipalities of Elmali, Duzce, Korkuteli, and Boztepe, Turkey, duplicated the successful pilot program within the next 2 years. To expand the training to more women farmers, we partnered with colleagues in Germany, Spain, and Malta to develop Empowering Women Farmers with Agricultural Business Management Training (EMWOFA), which had a multiplier effect by training educators who then trained women farmers to improve their business skills. The outputs of EMWOFA were a training manual for educators, a workbook for the women farmers, and e-learning videos in English, Turkish, Spanish, German, and Maltese.

In commercial interior green walls, plant trimming and replacement necessitated by stem elongation under low interior light levels is labor intensive and costly. Antigibberellin plant growth regulators (PGRs) may slow stem elongation and thus reduce maintenance costs in this environment. In Expt. 1, two PGRs were applied as foliar spray or drench to three spiderwort selections [two of zebra plant (Tradescantia zebrina) and one of inch plant (Tradescantia fluminensis)] immediately before installation in a green wall, each at three rates: ancymidol (ANC) foliar spray at 25, 100, and 200 mg·L⁻¹; paclobutrazol (PBZ) foliar spray at 20, 80, and 160 mg·L⁻¹; and PBZ drench at 1, 4, and 8 mg·L⁻¹, along with an untreated control. In Expt. 2, 80 mg·L⁻¹ PBZ foliar spray, 1 mg·L⁻¹ PBZ applied via subirrigation four times, and the combination of these two treatments, was evaluated on ‘Burgundy’ zebra plant. In both experiments, plants were placed in a vertical modular tray interior green wall. Change in total stem and specific internode length were measured every 14 days after installation for 3 months to calculate growth per month. Antigibberellin application slowed internode elongation of spiderwort selections during the first month after installation. Antigibberellins were more effective in zebra plant at reducing overall stem growth rate and less so on inch plant. Across the three spiderwort selections, 25 mg·L⁻¹ foliar spray of ANC resulted in no difference in growth rate when compared with the control, although 100 to 200 mg·L⁻¹ foliar spray was effective. Based on the results of both experiments, moderate and high rates of PBZ, applied both as a foliar spray and drench, resulted in similar reduction in stem elongation. PBZ applied as 20 to 80 mg·L⁻¹ foliar spray, 4 mg·L⁻¹ drench before installation in the wall, or a combination of an 80 mg·L⁻¹ PBZ pre-installation foliar spray and recurring 1 mg·L⁻¹ via subirrigation (four times) were effective at growth suppression of spiderworts for at least 3 months. Even rates of PBZ of 160 mg·L⁻¹ foliar spray or 8 mg·L⁻¹ drench did not show phytotoxicity in treated plants and could be considered for use. We recommend a pre-installation application of 80 mg·L⁻¹ foliar spray or 4 mg·L⁻¹ drench for controlling stem growth across spiderwort selections. Application of antigibberellin PGRs to plants before installation in green walls slows stem growth and can contribute to reduced maintenance costs.

Golf facilities account for 2.3 million acres in the United States. Numerous turfgrass species are managed on US golf facilities, but golf facilities may change turfgrasses depending on numerous variables. Knowing which turfgrasses are grown and how turfgrass selection has changed would provide important information to scientists, turfgrass managers, and policymakers. The objective of this survey was to measure turfgrass use on US golf facilities in 2021 and to determine whether changes in turfgrass selection have occurred since 2005. A survey was developed and distributed via e-mail to 13,938 US golf facilities, with 1861 responding. From 2005 to 2021, the total projected area of maintained turfgrass on US golf facilities decreased by 14.2%, which was likely a result of course closures and maintenance operations. Nationally, bermudagrass (Cynodon sp.) and Kentucky bluegrass (Poa pratensis) remained the most common warm- and cool-season turfgrasses, respectively. The area of winter-overseeded turfgrass declined by 60% between 2005 and 2021. The percentage of golf facilities that used zoysiagrass (Zoysia sp.) and seashore paspalum (Paspalum vaginatum) increased depending on region and specific playing surface, albeit a pragmatically minor increase. In general, turfgrass selection on golf facilities in northern climates did not change, whereas turfgrass selection in southern climates favored a change from cool- to warm-season species, depending on the playing surface. Whether in historically cool-season or warm-season regions, it appears that many golf facilities are exploring alternatives to their traditional turfgrass species.

Industrial insect rearing is expected to increase as a feedstock to meet growing global food demand. This will lead to greater production of insect excreta known as frass, a nutrient-dense organic material that has shown promise as a natural fertilizer source with potential environmental benefits. In this study, black soldier fly (Hermetia illucens) frass (BSFF) was compared with a synthetic fertilizer (SF) during production of containerized ornamentals grown under greenhouse conditions. Fertilizers were incorporated into a bark-based substrate at 0, 0.1, 0.2, or 0.3 kg⋅m^–3 nitrogen (N) planted with coleus (Plectranthus scutellarioides) plugs. Growth index, shoot dry weight, and leaf quality were assessed for a period of 6 weeks. In addition, coleus fertilized at 0.3 kg⋅m^–3 N and a control had leachate collected and analyzed weekly for volume, pH, electrical conductivity, and nutrient losses. Black soldier fly frass was found to produce marketable coleus plants at 0.3 kg⋅m^–3 N and reduce cumulative N leaching by 87% compared with coleus fertilized with SF at the same rate. Therefore, BSFF can be a suitable fertilizer source for coleus production without compromising growth and leaf quality while potentially decreasing nutrient leaching losses.

Surveys of blueberry [rabbiteye blueberry (Vaccinium virgatum) and southern highbush blueberry (Vaccinium corymbosum interspecific hybrids)] nurseries in the State of Georgia, USA, were conducted in 2007 and 2022 to determine the prevalence of and associations among propagation practices, especially related to disease management. As indicated by the reduction in surveyed nurseries in 2022 (7) compared with 2007 (18), the Georgia blueberry nursery industry has consolidated. However, cultural disease management practices have generally improved in these remaining nurseries. In 2007, in nurseries where cuttings were grown in containers, 77.8% reused containers and 66.7% did not sterilize them before use. The growing medium [pine (Pinus sp.) bark] was reused for subsequent production cycles in 29.4% of nurseries, although such reuse of media tended to be associated with production in beds as opposed to containers (P = 0.08). Nurseries used well water in 88.2% and pond water in 11.8% of cases. Cuttings were grown on benches (vs. the ground) in slightly fewer than half of the nurseries. In contrast, all nurseries surveyed in 2022 grew their cuttings in containers, used well water, and had increased bench use, albeit only slightly. Although all nurseries reused containers, only 28.5% did not sterilize containers before use, and only 14.3% of nurseries reported reusing media. Most nurseries surveyed in 2007 (83.3%) were on a routine, calendar-based fungicide program using a.i. targeted primarily against aboveground diseases (blights and leaf spots) and secondarily against soil-borne water molds (Phytophthora and Pythium species of the Oomycetes class). In contrast, 42.8% of those surveyed in 2022 were on a 2- to 3-week spray schedule, 42.8% used fungicides on an as-needed basis, and 14.4% were on a monthly schedule, indicating that fungicide scheduling varied dramatically among the remaining nurseries.

Growers have traditionally used mechanical pinching and other cultural practices to control height and encourage branching for full and uniform poinsettia (Euphorbia pulcherrima) plants. A total of six experiments were conducted over 5 years to evaluate the impact of chemically treating poinsettia on final height, branching, first color, visible bud formation, and anthesis. The first four experiments evaluated the potential of benzyladenine (BA) and gibberellins [GA₍₄₊₇₎] to increase height of treated poinsettia. Timing of the application was assessed during Expt. 1 using a combined concentration of 3 ppm BA and 3 ppm GA₍₄₊₇₎ applied at 5, 7, 9, or 11 weeks after pinching; some cultivars exhibited significantly more elongated inflorescences when treatment occurred 7 or 9 weeks after pinching. The application method and frequency was assessed during Expt. 2, and treatments were applied one or three times with either drench application at a concentration of 2 ppm or foliar application at a concentration of 5 ppm or untreated controls. All plants treated with three drench applications produced taller plants on average than when only applied once or when treated with a foliar application. Expt. 3 further assessed height gain and effects on flowering during late-season production with foliar applications of BA+GA_(4 + 7) applied 2 weeks after first color at a concentration of 2 ppm compared with untreated control plants. One cultivar, Mars Red, was observed to have a significant decrease in days to anthesis when treated (9 days) compared with untreated plants, but no cultivars exhibited a significant change in height resulting from treatment. Expt. 4 assessed both the application method (foliar and drench) and change in final environment when plants were either maintained in a greenhouse or relocated to a postharvest room before anthesis. Most cultivars experienced a significant height increase when treated with foliar application of BA+GA_(4 + 7) regardless of the final environment, but a significant delay in days to first color, visible bud, and anthesis was prevalent, and only one cultivar exhibited a treatment benefit from drench application with no significant delay in flowering or differences caused by changing environment. Expts. 5 and 6 were conducted over 2 growing years to evaluate the benefits of chemically pinching poinsettia using dikegulac sodium at a concentration of 800 ppm applied either once or twice (1 week apart) or 1600 ppm applied once to promote branching. The tallest plants were those treated one time at a concentration of 800 ppm showing lack of dominance in the apical meristem. The greatest number of shoots occurred when plants were treated with 800 ppm twice, whereas one application of 800 or 1600 ppm often, but not always, resulted in more shoots compared with mechanically pinched plants. Interestingly, the increased number of shoots from treated plants was often more than double the number compared with mechanical pinching, but those additional shoots failed to develop, which resulted in only one or two additional inflorescences. Production time was found to be a tradeoff because most dikegulac sodium-treated plants experienced an increased number of days to first color, visible bud, and/or anthesis. These results demonstrate that height control, whether to encourage stem elongation or halt apical dominance, is cultivar-specific, and that although both the method and concentration may be determined uniformly on some cultivars, the timing of application is crucial because of potential delays in floral development.

Florida has a long association with citrus (Citrus sp.) production. However, the citrus industry in Florida has been devastated by Huanglongbing (HLB) or citrus greening disease (Candidatus Liberibacter asiaticus). HLB affects the citrus tree phloem and eventually causes tree death. Cover crops, or noncash crops, have traditionally been used in row crop production to improve soil organic matter, for nitrogen fixing, and for weed control. Citrus growers may benefit from adopting cover crops because healthier soils could improve yields and fruit quality of citrus trees. However, growers are uncertain about the costs and benefits associated with cover crop investments. The objective of our study was to analyze whether cover crops represent an economically feasible option for Florida citrus growers. We calculated the break-even prices for ‘Valencia’ and non-‘Valencia’ oranges (Citrus sinensis) in terms of price per box (equivalent to 90 lb of oranges in Florida) and price per pound solids per box (amount of soluble solids per box of oranges) by considering additional costs and short-term savings from using cover crops across various yield and quality scenarios based on the past 10 years of data. Considering the short-term savings from adopting cover crops, the per-acre cost of production increased by $107.3/acre or by 5.73% and constituted 5.42% of the total production cost during the first year of adoption. After the 2018–19 peak, the yield and quality for both ‘Valencia’ and non-‘Valencia’ oranges have decreased steadily. Adopting cover crops in the current yield–quality scenario will not be profitable for either ‘Valencia’ or non-‘Valencia’ oranges. However, for ‘Valencia’ oranges, at the median yield and quality levels of 193.5 boxes/acre and 6.08 lb solids/box, respectively, cover crop adoption would be profitable because the break-even price of $2.25/lb solids would be comparable to the market prices of the past 5 years.