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The effects of paclobutrazol (PBZ), a plant growth retardant, and average daily temperature (ADT) on geranium (Pelargonium ×hortorum), petunia (Petunia ×hybrida), marigold (Tagetes erecta), and pineapple mint (Mentha suaveolens) were quantified. Treatments consisted of four PBZ spray concentrations (0, 15, 30, or 45 ppm) and three ADTs (constant day and night greenhouse temperatures set to 16, 22, or 28 °C). The effectiveness of PBZ was dependent on species. Greenhouse ADT was significant for all species for both growth index (GI) and dry weight (DW). Whether the GI or DW was impacted by the interaction between ADT and PBZ levels were also species dependent. As ADT increased, the trialed levels of PBZ were less effective. Three species (all but petunia) had a significant ADT and PBZ interaction for DW. The 0 ppm PBZ treatment for geranium exhibited a larger DW at 28 °C compared with 16 °C, whereas the 30 and 45 ppm PBZ treatments each had smaller DWs at 28 °C than at 16 °C. However, marigold and pineapple mint generally had larger DWs at higher ADTs than lower ADTs within a PBZ treatment.

Because the waterproofing membrane beneath green roofs is estimated to last at least 45 years, long-term plant performance beyond initial establishment is critical. Plants that survive initially on a green roof may not exist in the long term because of variability in climate and other factors. This study evaluated the effect of green roof substrate depth on substrate moisture, plant stress as measured by chlorophyll fluorescence, and plant community development and survival of 12 Sedum species over 4 years in a midwestern U.S. climate during 4 years of growth. Plugs of 12 species of Sedum were planted on 8 June 2005 and evaluated biweekly for absolute cover (AC). Most species exhibited greater growth and coverage at a substrate depth of 7.0 cm and 10.0 cm relative to 4.0 cm. For the species evaluated, substrate depths of at least 7.0 cm are highly recommended. AC of Sedum was significantly greater at this substrate depth than at 4.0 cm. Mean volumetric moisture content of the three substrate depths followed the same pattern as AC. When averaged over time, the 4.0-cm substrate depth held less moisture than depths of 7.0 or 10.0 cm, whereas the 7.0- and 10.0-cm substrate depths were statistically the same. Species exhibiting the greatest AC at all substrate depths were S. floriferum, S. sexangulare, S. spurium ‘John Creech’, and S. stefco. In general, species that are less suitable at these substrate depths are S. ‘Angelina’, S. cauticola ‘Lidakense’, S. ewersii, S. ochroleucum, and S. reflexum ‘Blue Spruce’.

As forests, agricultural fields, and suburban and urban lands are replaced with impervious surfaces resulting from development, the necessity to recover green space is becoming increasingly critical to maintain environmental quality. Vegetated or green roofs are one potential remedy for this problem. Establishing plant material on rooftops provides numerous ecological and economic benefits, including stormwater management, energy conservation, mitigation of the urban heat island effect, and increased longevity of roofing membranes, as well as providing a more aesthetically pleasing environment in which to work and live. Furthermore, the construction and maintenance of green roofs provide business opportunities for nurseries, landscape contractors, irrigation specialists, and other green industry members while addressing the issues of environmental stewardship. This paper is a review of current knowledge regarding the benefits of green roofs, plant selection and culture, and barriers to their acceptance in the United States. Because of building weight restrictions and costs, shallow-substrate extensive roofs are much more common than deeper intensive roofs. Therefore, the focus of this review is primarily on extensive green roofs.

The objectives of this study were to survey Midwest consumers to assess their willingness to buy alternatives to Impatiens walleriana given the confirmed presence of Impatiens downy mildew (IDM; Plasmopara obducens) in Michigan landscapes in 2012. An Internet survey queried consumers from four states (Illinois, Indiana, Michigan, and Ohio) and questions consisted of likelihood to buy, purchasing characteristics considered, impatiens purchases in 2012, and demographic questions. Roughly 500 participants per state responded and almost three-fourths (73.8%) of respondents said they planted impatiens in their landscape in 2012. Of the 16.4% who said their plants did not look healthy at the end of the growing season, 69.3% self-identified the plant as having IDM symptoms. Purchasing characteristics that had the highest mean scores were bloom period, flower color, and longevity, whereas the lowest mean scores were for compact shape with no spindly growth, fragrance, and locally grown. Three impatiens alternative species were acceptable alternatives (scored a positive utility in the conjoint analysis) for shade-tolerant species. Begonia semperflorens was the most preferred followed by Browallia speciosa and then Impatiens hawkeri. Solenostemon scutellarioides was the least preferred. Three impatiens alternative species also scored a positive utility in the conjoint analysis and would serve well for partial shade-tolerant species. Heliotropium arborescens was the most preferred followed by Salvia splendens and then Lobelia erinus. Hypoestes phyllostachya and Iresine herbstii were preferred least as impatiens alternatives. The attribute with the highest relative importance was species for both conjoint analyses, whereas the price attribute was the least important.

Christmas tree and poinsettia (Euphorbia pulcherrima) sales are static or declining nationally and in Michigan. The objectives of this project were to evaluate a “buy local” educational media campaign (“Make it a Real Michigan Christmas”) designed to increase sales of poinsettias and Christmas trees. Consumer online surveys were administered four separate times (Oct. 2011, Jan. 2012, Oct. 2012, and Jan. 2013) to collect measures of awareness and knowledge both before and after each year’s educational media campaign. The survey asked Michigan residents about their Christmas tree and flowering plant purchases for the holiday, Christmas attitudinal questions (scored on a five-point Likert scale), awareness of this campaign, and demographic information. There were 1712 respondents, roughly split into a quarter per survey. Most measures of demographics and purchasing habits were very similar across the four sampling times. A little over a quarter (28% to 30%) purchased a Christmas tree the previous holiday, 16% to 20% which were live trees and 9% to 10% were artificial trees. Roughly a third (31% to 39%) of respondents purchased live poinsettias the previous holiday. “Make it a Real Michigan Christmas” had 3.3% to 5.0% of consumer awareness. Factor analysis identified two key attitudinal dimensions of the Christmas holiday. Factor 1 was described as a dimension of live Christmas trees being difficult, whereas Factor 2 showed a dimension of live trees being worth the effort. Participants were segregated into four clusters based on their factor scores. Emerging groups were either low/high on factor 1 (live trees are difficult) and/or factor 2 (live trees worth the effort). Few demographic differences were identified between the four groups, indicating they are relatively homogeneous in demographic composition. The largest group produced in the cluster analysis was 44% of the sample (cluster 1) and those consumers were more focused on the difficulty of live-tree purchases while the smallest group (6%, cluster 3) had factor scores less than 0 for both attributes.

The objectives of this study were to determine the effectiveness of using animal tissue compost (ATC) as a substrate amendment for ornamental plant container production. The compost was produced using soiled sawdust bedding mixed with assorted animal tissues and actively composted for at least 6 months and cured for 6 to 10 months. Five substrate treatments that consisted of four different ratios of ATC and Canadian sphagnum peatmoss were formulated, all containing 20% medium grade horticultural perlite. Four species [geranium (Pelargonium ×hortorum ‘Maverick Red’), marigold (Tagetes erecta ‘Inca II Yellow’), pansy (Viola ×wittrockiana ‘Delta Premium Yellow Blotch’), and petunia (Petunia ×hybrida ‘Prostrate Wave Purple Improved’)] were evaluated with weekly plant measurements. Geranium and petunia exhibited 100% survival for all treatments. Marigold and pansy showed 100% survival for the control treatment (0% ATC) and the treatment with the smallest amount of ATC (20% ATC). Treatments for pansy and marigold with more than 40% ATC exhibited 40% to 90% survival. All ATC substrate treatments produced the same number of flowers and buds as the control in geranium, marigold, and petunia, while the treatments containing 20% to 60% of ATC for pansy exhibited more flowers and buds than the control. Measurements of pH and electrical conductivity (EC) varied based on treatment. Based on the species and the ratios of peat, ATC, and perlite tested here, ATC has the potential to be a peat extender in floriculture substrates when used in ratios of 20% or less.

Neonicotinoids have recently been implicated by the media as a contributing factor to the decline of honey and bumblebees. We sought to better understand consumer perceptions and willingness to pay for traditional, neonicotinoid-free, bee-friendly, or biological control pest management practices as growers may seek alternative management practices to systemetic insecticides. We conducted a nationwide Internet survey (n = 3082), where consumers answered attitudinal, comprehension, likelihood-to-buy, and demographical questions about indoor (marketed in 10-cm pots) and outdoor (marketed in 30-cm hanging baskets or 10-cm pots) floriculture products. The likelihood-to-buy questions were analyzed using conjoint analysis to determine which attributes had the greatest part-worth scores or which ones were viewed most positively by survey respondents. Of the total participants, 65.1% (n = 2002) of the subjects had purchased an annual flowering plant in the 12 months before the survey. Respondents reported that the most important plant health and appearance factors that affect their purchasing decisions were that the flowering plants have no plant damage, while the second most important factor was that plants have no insects on them. The least important factor in the ranking of stated importance was that no neonicotinoid insecticides were used during the production of the plant. This finding may have resulted from 56.6% of all participants who reported that they did not understand the term. For those who viewed the indoor 10-cm flowering plants (n = 1052), the plant species accounted for 41.2% of the decision to purchase the plant, followed by production type (32.8%) and price (26.0%). All three product attributes were of equal importance to the subjects who viewed the outdoor 10-cm flowering plants (n = 1024), whereas only price had a lower relative importance when compared with production type and species for those who viewed the 30-cm hanging baskets (n = 1006). Across all three studies, use of the term “bee-friendly” had the greatest economic value because it had the highest part-worth utility score, or the greatest willingness-to-buy. For the subjects who viewed the outdoor plants, “bee-friendly” and “use of beneficial insects” had greater economic value (with positive part-worth utility scores), but “neonicotinoid-free” and “traditional insect control” both had negative part-worth utility scores, indicating they were valued less and detracted from the dollar value of the plant. The term “bee-friendly” was worth up to five times more to those respondents that had bought a plant in the last 12 months compared with those who had not. Therefore, if ornamental plants are labeled with pest management practices, most consumers value the term “bee-friendly” more and will likely discount products labeled “neonicotinoid-free.”

Sales of many products, including umbrellas and skis, depend on weather conditions. Anecdotal evidence from plant producers and retailers indicate that their sales are also heavily reliant on weather conditions. Still, little published literature documents weather's influence on plant sales. Daily sales data of herbs, vegetables, and flowering annuals were acquired from 42 retail stores in Indiana, Ohio, and Michigan (which were divided into four regions based on zip code). The multisite Midwestern retailer sells food and household items year-round but seasonally sells plants in outdoor covered areas. The data were analyzed using time series regression and the model produced significant results, but the amount of variance captured by region, weather parameters, month, and day of the week was only ≈40% for herbs and vegetables (H+V) and flowering annual plants (FA). Precipitation amount had no effect on sales of H+V and FA, likely because the plants were merchandised under cover. Increasing units of sunshine lowered sales by 1%. H+V sales were greatest in the southeast Michigan region but for FA were greatest in the mid-Michigan region. Lower minimum air temperature reduced sales for sales of both H+V and FA, whereas higher maximum air temperature increased sales. Sales were substantially higher in May and lower in June and July compared with April. Sales were higher in 2009 than 2007. Compared with Wednesday, sales were higher everyday and highest on Saturday. Day of week and month had a greater impact on sales than did any weather parameter. Thus, region, weather, month, and weekday do influence daily plant sales but did not account for most of the variability in 42 U.S. midwestern retail outlets.

Declining bee populations has garnered media attention, which has pressured plant retailers to ask or demand the reduction or elimination of neonicotinoid insecticide use in greenhouse production. This study investigated consumer perspectives on eco-friendly ornamental plant production practices in combination with a variety of insect management practices. Data from an online study were collected from 1555 Americans in May 2015. Over half (55%), nearly half (48.2%), and more than 30% of the participants felt that “bees are not harmed,” “better for the environment,” or “plants that attract bees,” respectively, was a characteristic of bee-friendly insect management practices. The latter group erroneously confused bee-friendly insect management practices with plants that are a potential food source for bees. When asked to rate various insect management plant production practices on a five-point Likert scale, consumer mean scores were positive (defined here as 3.5 to 5.0) for “plants grown using bee-friendly insect management practices,” “plants grown using insect management strategies that are safe for pollinators,” “plants grown using best insect management practices to protect pollinators,” and “plants grown using insect management practices that leaves no insecticide residue on the plant.” Plant species accounted for 31.6% of the decision to purchase the plant, followed by price (25.1%), insect management strategy (23.3%), and eco-friendly practices (20.1%) that was similar to prior published findings. Analyses showed that plants labeled as “grown using bee-friendly insect management practices” were worth $0.26, $0.26, $0.89, and $1.15 more than plants labeled as “grown in a sustainably produced potting soil/mix,” “grown using recycled/recaptured water,” “grown using protective neonicotinoid insecticides,” and “grown using traditional insect management practices,” respectively. In addition, plants labeled as “grown using best insect management practices to protect pollinators” were worth $0.10, $0.10, $0.73, and $0.99 more than plants labeled as “grown in a sustainably produced potting soil/mix,” “grown using recycled/recaptured water,” “grown using protective neonicotinoid insecticides,” and “grown using traditional insect management practices,” respectively. Thus, selected insect management strategies were valued more, on average, than eco-friendly production practices.

Eye-tracking equipment is now affordable and portable, making it a practical instrument for consumer research. Engineered to best analyze gaze on a plane (e.g., a retail shelf), both portable eye-tracking glasses and computer monitor–mounted hardware can play key roles in analyzing merchandise displays to better understand what consumers view. Researchers and practitioners can use that information to improve the sales efficacy of displays. Eye-tracking hardware was nearly exclusively used to investigate the reading process but can now be used for a broader range of study, namely in retail settings. This article presents an approach to using glasses eye tracker (GET) and light eye tracker (LET) eye-tracking hardware for applied consumer research in the field. We outline equipment use, study construction, data extraction as well as benefits and limitations of the technology collected from several pilot studies.