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Biosolids are rich in plant nutrients and are a byproduct of municipal wastewater treatment and those that meet strict government safety standards can be land applied in most agricultural settings except for the U.S. Department of Agriculture (USDA) certified organic production. Across the United States, about 60% of biosolids are land applied, but in Mississippi almost no biosolids are land applied. Our research goal was to compare plant size in southeastern U.S. soils amended with biosolids at rates of 2, 8, 14, and 20 tons/acre in contrast to soils amended with synthetic fertilizers using 'Floral Lace Cherry' dianthus (Dianthus chinensis × barbatus), 'Dreams Coral Morn' petunia (Petunia × hybrida), 'Pidgeon White' kale (Brassica oleraceae var. acephala), and 'Bright Lights' swiss chard (Beta vulgaris ssp. cicla). To accomplish this, fertilizers and biosolids were applied to prebedded fields in a randomized complete block design with a split-plot arrangement of nutrient treatments. Plant performance data and soil data were taken 43 and 56 days after transplant. Soil pH was reduced and organic matter increased at the highest application rates (14 and 20 tons/acre) of biosolids, and higher levels of phosphorus, zinc, and sulfur were found in these soils. In plant shoots, higher levels of copper, manganese, magnesium, and zinc were found when grown in soils amended with biosolids at a rate of 20 tons/acre compared with plants grown with synthetic fertilizers. Except for swiss chard, no crops fertilized with biosolids exhibited a difference in dry weights (DW) compared with conventional fertilizers. These data demonstrate that soil properties can be improved and similar plant sizes can be achieved through biosolid applications. We conclude that Grade A biosolids produced in Mississippi can be used to supplement synthetic fertilizers for ornamental and vegetable production. [ABSTRACT FROM AUTHOR]

The effects of paclobutrazol (PBZ), a plant growth retardant, and average daily temperature (ADT) on geranium (Pelargonium xhortorum), petunia (Petunia, xhybrida), marigold (Tayjetes 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 n ight 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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The influence of several environmental and cultural factors on the efficacy of paclobutrazol liner dips were evaluated for three species of bedding plants: 'Fancy' scaevola (Scaevola aemula), 'Suncatcher Plum' petunia (Petunia xhybrida), and 'Double Fiesta Rose' impatiens (Impatiens walleriana). The impact of paclobutrazol concentration in the dip solution, location of treatment, root substrate moisture status, and time in the dip solution were investigated. Before the liner dip application, the rooting substrate was brought to a specific percentage of container water capacity (20%-100%). Liners were then dipped in a paclobutrazol solution of the prescribed concentration (1-16 mg·L-1) for a prescribed time interval (10-300 s) in a specific location (open-wall greenhouse, polyethylene-glazed greenhouse under 80% shade fabric, three-wall potting shed, or building interior). Plant size data were collected when the untreated control plants reached a marketable stage. Paclobutrazol concentration and root substrate moisture status had a significant effect on size control, but location and dip duration did not. Size suppression varied by species. Following a liner dip at 2 mg·L-1, scaevola, impatiens, and petunia plants were 44%, 26%, and 11% smaller than the untreated controls, respectively. Petunia plants dipped in a 8 mg·L-1 paclobutrazol solution with substrate moisture status of 100%, 90%, 80%, 70%, 50%, or 20% of container capacity were 11%, 8%, 25%, 30%, 41%, or 42% smaller than the untreated control, respectively (30 s dip duration, open-wall greenhouse). Petunia plants dipped in a solution of 8 mg·L-1 paclobutrazol for 10, 30, 120, or 300 s were all between 18% and 23% smaller than the control (50% of container capacity, open-wall greenhouse). Petunia plants dipped in an 8 mg·L-1 paclobutrazol solution in all four locations were all 20% to 21% smaller than the untreated control. [ABSTRACT FROM AUTHOR]

Twenty-one cultivars of vegetative annuals were treated with 0%, 50%, or 100% of the production fertilization rate of 300 mg·L-1 N starting 2 weeks before and continuing until harvest. At harvest, plant width, flower number, and quality rating were measured. The plants were then placed in a simulated interior environment where flower number was counted and quality rating was assigned to each plant weekly for 3 weeks. Overall, 14% of the cultivars maintained a marketable quality (i.e., quality rating of>3.0 of 5) for 3 weeks, 43% for 2 weeks, 38% for 1 week, and one cultivar did not maintain quality during the postharvest evaluation. Reduced end-of-production fertilization rate (EPFR) resulted in higher quality ratings for at least one additional week of simulated shelf life for three cultivars, including 'Dreamtime Copper' bracteantha (Bracteantha braeteata), 'Vanilla Sachet' nemesia (Nemesia xhybrida), and 'Bridal Showers' sutera (Sutera hybrida). 'Comet White' and 'Sunlight' argyranthemum (Argyranthemum frutescens) retained flowers an additional 2 weeks and 'Caritas Lavender' angelonia (Angelonia angustifolia), 'Dreamtime Copper' bracteantha, 'Liricashowers Deep Blue Imp.' and 'Starlette Trailing Purple' calibrachoa (Calibrachoa hybrid), 'Vanilla Sachet' nemesia, 'Cascadias Pink' petunia (Petunia xhybrida), and 'Bridal Showers' sutera retained flowers an additional 1 week when treated with 0% compared with 50% or 100% EPFR. Four cultivars had decreased plant width at harvest with 0% EPFR. These results indicate that reducing fertilization 2 weeks before harvest can prolong shelf life of some vegetative annuals. Differences in the length of shelf life and responses to reduced EPFR occurred among cultivars of all the affected species. Reduced EPFR did not increase the shelf life of two species, including diascia (Diascia xhybrida) and lantana (Lantana camara). [ABSTRACT FROM AUTHOR]

The objective of this study was to quantify water volume and nutrient content leached during propagation of herbaceous cuttings in commercial greenhouses. Nutrient concentrations in the fertigation solution, substrate, tissue, and leachate were measured between Jan. and Mar. 2006 at eight greenhouse locations in Michigan, Colorado, New Hampshire, and New Jersey. Grower management of the timing and concentration of nutrients applied to vegetatively grown calibrachoa ( Calibrachoa x hybrida) or petunia (Petunia x hybrida) liner trays varied among the eight locations, ranging from 0.5 to 80 mg·L-1 nitrogen (N) in week 1 and from 64 to 158 mg·L-1 N in week 4. Over a 4-week crop period, applied nutrients averaged 4.9 g·m-2 N, 0.8 g·m-2 phosphorus (P), and 5.8 g·m-2 potassium (K), and leached nutrients averaged 1.1 g·m-2 N, 0.3 g·m-2 P, and 1.6 g·m-2 K. Leaching of nutrients and irrigation water was highly variable among locations. Leached water volumes ranged from 4.5 to 46.1 L·m-2 over 4 weeks and contained 0.29 to 1.81 g·m-2 N, 0.11 to 0.45 g·m-2 P, and 0.76 to 2.86 g·m-2 K. The broad range in current commercial fertigation practices, including timing of nutrient supply, concentration of applied fertilizer, and leaching volume, indicate considerable potential to improve efficiency of water and fertilization resources during propagation and reduce runoff. [ABSTRACT FROM AUTHOR]

An increasingly popular technique for applying plant growth regulators (PGRs) to floriculture crops is to dip or soak the root medium of" a transplant in a chemical solution before transplanting. This PGR application method, termed a "liner dip," can be an effective height-control strategy, for greenhouse crop production. However, few studies have quantified how bedding plant species respond to different chemicals and application rates. Argyranthemum (Argyranthemum x hybrida 'Sunlight'), calilirachoa (Calibraehoa x hybrida 'Callic Dark Blue'), petunia (Petunia xhybrida 'Cascadias Vivid Red'), scaevola (Scaevola albida 'Jacob's White'), and verbena (Verbena xhybrida 'Rapunzel Red') liners were dipped in paclobutrazol at 4, g, or 16 mg⋅L-1 or in uniconazole at 2, 4, or 8 mg ⋅ L-1 for 30 seconds and subsequently transplanted into 4.5-inch-diameter round pots. At 28 days after transplant, all rates of paclobutrazol and uniconazole inhibited subsequent stem elongation by 21% to 67% in calibrachoa, petunia, scaevola, and verbena. In argyranthemum, stems were 33% to 42% shorter in plants treated with paclobutrazol at 8 or 16 mg⋅L-1 or uniconazole at all rates. In some species, the liner dip delayed flowering and reduced flower number compared with that of nontreated plants. This pretransplant PGR application technique can be usefid on vigorous ornamental species when grown together in the same container with less aggressive species without a PGR application. [ABSTRACT FROM AUTHOR]

Growth of 'Aladdin Peach Morn' petunia (Petunia × hybrida) and 'Accent White' impatiens (Impatiens wallerana) was compared in substrates containing 0%, 30%, 60%, or 100% compost made from biosolids and yard trimmings and fertilized with Nutricote Total 13-13-13 (13N-5.7P-10.8K) Types 70, 100, and I40 incorporated at rates of 0.5x, 1x, 2x, or 3x (x = standard application rate for a medium-feeding crop). Petunia shoot dry weight of plants fertilized with Type 70 incorporated at 0.5x increased as the percentage of compost in the substrate increased from 0% to 60% and then decreased, while shoot dry weight of plants fertilized with Type 70 incorporated at 1x, 2x, or 3x increased as the percentage of compost increased from 0% to 30% and then decreased. Impatiens shoot dry weight of plants fertilized with Type 70 incorporated at 0.5x and 1x also increased as the percentage of compost increased from 0% to 30% and then decreased, while shoot dry weight of plants fertilized at 2x and 3x decreased as the percentage of compost increased from 0% to 100%. Both petunia and impatiens shoot dry weight of plants fertilized with Type 100 and Type 140 incorporated at 0.5x, 1x, 2x, or 3x increased as the percentage of compost increased from 0% to 60% and then decreased. [ABSTRACT FROM AUTHOR]