ASHS 2024 Conference: Full Schedule

12:45pm HST

FLOR - Peperomia mauiensis can tolerate low indoor light conditions for up to 12 months

Wednesday September 25, 2024 12:45pm - 12:55pm HST

Peperomia mauiensis is an endemic peperomia found on west Maui, and the islands of Molokai and Lanai. Its short stature and reddish stems and leaves make it highly ornamental. To evaluate its feasibility as an indoor foliage plant, potted plants (n=6) were grown under three light levels (0.2 mol·m-2·d-1 [low], 0.4 mol·m-2·d-1 [office] and 2.9 mol·m-2·d-1 [high] for 12 hours) in airconditioned settings (22°C, 61% RH) for 1 year. Plant height and diameter as well as visual quality [1 = poor, 2 = fair (not saleable), 3 = acceptable (saleable), 4 = good, and 5 = excellent quality) were recorded 0, 3, 6 and 12 months after placing in light chambers. Height and diameter of plants between light treatments were similar at 0 (height = 5.9 cm; diameter = 10.5 cm) and 3 (height = 7.1 cm and diameter = 15.0 cm) months after the plants were placed in light chambers. Visual quality ratings also did not differ between light treatments at 0 (3.5) and after 3 (3.6) months. After 6 months, plants under office light conditions were the tallest (10.8 cm) and the widest (18.2 cm). Visual quality ratings between treatments at 6 months were similar (3.4). At 12 months, plant height between treatments were similar (8.8 cm), but office light plants exhibited the widest diameter (23.2 cm). Visual quality ratings between treatments at 12 months were similar (2.1) but was no longer acceptable. Results of the study indicate that Peperomia mauiensis can tolerate low indoor light levels and can be used as an indoor potted foliage plant.

Speakers

Orville Baldos

University of Hawaii at Manoa

Co-authors

Christyn Wong

Hawaii Department of Agriculture

Lindsey Watanabe

University of Hawaii at Manoa

Sherry Ann Hara

University of Hawaii at Manoa

Wednesday September 25, 2024 12:45pm - 12:55pm HST
Nautilus 1

Poster presentation (individual talk), Floriculture

SUBJECT Floriculture

12:55pm HST

FLOR - Effect of LED Lighting, Fertilization Rates and Gibberellin A3 Application to Greenhouse Grown Geranium (Pelargonium x hortorum) 'Red Maverick' Plants

Wednesday September 25, 2024 12:55pm - 1:05pm HST

Nautilus 1

The effect of LED lighting, fertilization rate and gibberellin application on geranium (Pelargonium x hortorum) 'Red Maverick' plants in a greenhouse setting was evaluated. Seeds were germinated in 288 plug trays, transplanted to 3-1/2 inch geranium pots in a peat-based media (ProMix) and grown in a greenhouse environment. Twelve treatments consisting of plants that received either no, 150 ppm or 300 ppm 20-20-20 weekly fertilizer applications following transplant, abmbient or LED (Phillips Red/Blue) greenhouse lighting, and a treatment of either no or 10 ppm gibberellin A3 (GA3; ProGibb) were evaluated by recording weekly height measurements, pH, electrical conductivity (EC), and floral bud appearance was recorded for each treatment. The tallest, most advanced plants were obtained from ambient light, high fertility and ProGibb application with the shortest plants were produced by the ambient light, no fertilization, and no gibberellin application treatment. Visible bud was first noticed in the LED light grown plants at low and high fertility with and without gibberellin application. The results of this study will aid greenhouse growers producing geranium crops under different greenhouse lighting conditions to consider fertility rates and gibberellin application to decrease the production time of geranium crops.

Speakers

Sonja Maki

University of Wisconsin-River Falls

Co-authors

Zachary Endreas

University of Wisconsin-River Falls

Wednesday September 25, 2024 12:55pm - 1:05pm HST
Nautilus 1

Poster presentation (individual talk), Floriculture

SUBJECT Floriculture

1:05pm HST

FLOR - Investigating the Effect of Hydrafiber and Biochar As a Substitute for Peat-based Substrate for Zinnia (Zinnia elegans)

Wednesday September 25, 2024 1:05pm - 1:15pm HST

Nautilus 1

The increasing environmental concerns and economic pressures necessitate the search for peat moss alternative as a substrate component, aiming to balance ecological sustainability with cost-effectiveness. This study aims to assess whether the biochar (BC) and hydrafiber (HF) could be a partially replacement for peat moss for zinnia and snapdragon production. Twelve substrates were formulated by either mixing BC (20%,40%, or 60% by vol) with HF (20%, 40%, or 60% (by vol), with the remaining being peat moss or blending BC (0%, 20%,40%, and 60%, by vol) with the commercial peat moss-based substrates (CS). The physical properties of substrate, including container capacity (CC), total porosity (TP), air space (AS), bulk density (BD), and water holding capacity (WHC), and chemical properties including leachate pH and electrical conductivity (EC) were measured. Plant growth parameters including growth index (GI) and leave greenness (indicated with SPAD value), biomass, and numbers of flowers were measured biweekly. The results showed all the substrate mixes had similar AP, BD and SPAD. Treatment with 20

Speakers

Lilin Chen

Graduate Research Assistant, University of Georgia

I'm interested in biochar effect on containerized plants, especially the effect under abiotic stresses such as drought and salinity.

Co-authors

Ping Yu

University of Georgia

Yulong Chen

The University of Georgia

Wednesday September 25, 2024 1:05pm - 1:15pm HST
Nautilus 1

Poster presentation (individual talk), Floriculture

SUBJECT Floriculture

1:15pm HST

FLOR - The Impact of Cold and Darkness on Osmanthus fragrans Flowering and Growth

Wednesday September 25, 2024 1:15pm - 1:25pm HST

Nautilus 1

Osmanthus fragrans, a culturally and economically significant plant in Asian countries, exhibits unique floral characteristics influenced by endogenous metabolites. Previous studies suggest its flowering timing and intensity may be affected by environmental factors including cold and darkness. This study aimed to investigate the effects of cold and darkness factors on the response of Osmanthus fragrans flowering and growth. This experiment included 7 cold and dark treatments (plants were sitting in the dark coolers from 0-15 days) and dark-only treatments (plants were sitting in the GH with plastic bags from 0-9 days). Plant responses were assessed based on the number of flowers, height, and width measurements on the 5th, 7th, 9th, 11th, 13th, and 15th days post-treatment. The results showed there was no significant difference in plant height across treatments. Dark-only treatment for 7 days significantly increased width growth compared to the control group (9 days), and dark-cold treatment for 5, 7, 9, 11, and 13 days. The increase in the number of flowers in the cold-dark treatment for 9 and 15 days was significantly higher than in other treatments, except for the control. In conclusion, the cold and darkness could promote flowering in Osmanthus fragrans without negatively affecting plant growth.

Speakers

Yulong Chen

The University of Georgia

Co-authors

Lilin Chen

The University of Georgia

Ping Yu

University of Georgia

Wednesday September 25, 2024 1:15pm - 1:25pm HST
Nautilus 1

Poster presentation (individual talk), Floriculture

SUBJECT Floriculture

1:25pm HST

FLOR - Growth and Quality of Four Zinnia Cultivars Grown in Eastern South Dakota

Wednesday September 25, 2024 1:25pm - 1:35pm HST

Nautilus 1

Over the past two decades, interest in local specialty cut flower production in Eastern South Dakota has grown with several new flower farms being established across the region. However, there is currently no local, research-based information available to support growers in this new wave of interest. The purpose of this study was to assess the production and quality of four zinnia cultivars grown in Eastern South Dakota to support local specialty cut flower growers in their operations. This was a randomized complete block study with four zinnia cultivars (Zinderella Peach, Oklahoma Ivory, Queen Red Lime, and Benary’s Giant Purple) grown in 2022 and 2023. Zinnias were started in the greenhouse and then transplanted into the field in early summer each season. Harvest began each year when flowers reached maturity (July), with one harvest event taking place each week until the first frost. Harvested flowers were rated as marketable or non-marketable based on categories of stem length (18 -inch-long, 13-17.99-inch-long, 8-12.99-inch-long, and

Speakers

Kristine Lang

South Dakota State University

Co-authors

Alexis Barnes

South Dakota State University

Ellen Fitzpatrick

South Dakota State University

Hannah Voye

South Dakota State University

Wednesday September 25, 2024 1:25pm - 1:35pm HST
Nautilus 1

Poster presentation (individual talk), Floriculture

SUBJECT Floriculture

1:35pm HST

FLOR - Effects of Photoperiod Treatments on Stock Plants and Cutting Rooting of Callirhoe involucrata

Wednesday September 25, 2024 1:35pm - 1:45pm HST

Nautilus 1

Effects of Photoperiod Treatments on Stock Plants and Cutting Rooting of Callirhoe involucrata James E. Klett and Ronda Koski Colorado State University Department of Horticulture and LA Production of attractive and desirable plants, native to the plains and prairies of central North America, can sometimes be limited due to problems associated with successful rooting of vegetative cuttings. Species that have a long period of bloom can be challenging to vegetatively propagate during the growing season, because sufficient juvenile (vegetatively) growth is necessary for high-quality cuttings. Callirhoe involucrata (winecups) is a native herbaceous perennial with sprawling stems, palmately divided leaves, and dark pink flowers that creates a long lasting, colorful groundcover in landscapes with limited or no supplemental irrigation. Winecups can be difficult to propagate due to seed dormancy and poor rooting of vegetative cuttings. Manipulating the growing conditions of stock plants to suppress reproductive growth may improve rooting success of vegetative cuttings. Based on previous research at Colorado State University with other ornamental perennials and programmed photoperiods, winecups were grown under three programmed photoperiods to determine if a particular photoperiod could be used to suppress reproductive growth and promote vegetative growth. The research was replicated three times, all conducted in a similar fashion, but at different times of the year. Results indicate that plants grown under 10-hour light and 8-hour light photoperiods remained vegetative longer when compared to plants grown under 12-hour photoperiod. Plants grown under 12-hour photoperiods had greater mean ending dry weight when compared to plants grown under 10 hour and 8-hour photoperiods. Cuttings harvested from plants grown under 8-hour photoperiod had higher percent rooting and greater number of roots per cutting when compared to vegetative cuttings harvested from plants grown under 12-hour photoperiod. Based on these research findings, plant propagators may be able to increase production of winecups by growing stock plants under 8-hour photoperiod.

Speakers

James Klett

Colorado State University

FLOR POSTER KLETT pdf

Wednesday September 25, 2024 1:35pm - 1:45pm HST
Nautilus 1

Poster presentation (individual talk), Floriculture

SUBJECT Floriculture

1:45pm HST

FLOR - Consumer testing and surveys indicate a market for Peperomia mauiensis, an endemic succulent with potential use as an indoor potted plant

Wednesday September 25, 2024 1:45pm - 1:55pm HST

Nautilus 1

Peperomia mauiensis is an endemic succulent found on the islands of Maui, Molokai and Lanai. Its reddish stems and foliage as well as its small stature make it a potential indoor ornamental plant. To assess consumer acceptance, a public plant giveaway with surveys was conducted. Fifty-six plants in plastic and ceramic pots were distributed to the public with the completion of a survey. A six-month follow up survey was conducted to assess the condition of the plant and obtain consumer feedback. During the plant giveaway, 77% of participants completed the survey. Nearly all respondents are willing to buy the plant and recommend it to friends and co-workers. Thirty percent of respondents are willing to buy the plant for $5 in a ceramic pot and $3 to $5 for a plastic pot. Six months after the giveaway, 39.5% of initial respondents completed the follow-up survey. About half of the respondents (52.9%) reported the plant was growing healthy and vigorous. The majority of the respondents did not fertilize the plant (81.3%) and did not report any pest (94.1%) and disease (88.2%) issues. Most responded that they liked it as a houseplant (88.2%) and it was easy to maintain (82.4%). Most respondents (35.3%) were willing to buy the plant again for $5. Results of the surveys indicate that there is consumer interest in Peperomia mauiensis as a new native indoor plant.

Speakers

Orville Baldos

University of Hawaii at Manoa

Co-authors

Hannah Lutgen

CTAHR

Wednesday September 25, 2024 1:45pm - 1:55pm HST
Nautilus 1

Poster presentation (individual talk), Floriculture

SUBJECT Floriculture

1:55pm HST

FLOR - Trials of Low Elevation Tolerant Leucospermum Hybrids on Oahu, HI

Wednesday September 25, 2024 1:55pm - 2:05pm HST

Nautilus 1

Leucospermum species are temperate climate plants native to South Africa and have restricted production regions in Hawaii limited to elevations of 457 m or higher. This limitation and competition for land has been partially responsible to a decline in Leucospermum production in Hawaii. Agriculture land at lower elevations is more abundant and cheaper, and is an option for growing low elevation tolerant varieties. Breeding programs at the University of Hawaii at Manoa have focused on developing hybrids that will perform to commercial standards for plant growth, yield and quality, and grow at or near sea level. 14 hybrids of Leucospermum were trialed at 152 m elevation on Oahu HI. 10 hybrids exhibited adequate survival and were selected for continued trial. Weahter, plant growth (height and width), flower count, flowering seasonality, and plant health data were collected from 2021-2023. Flower length and quality data, and vase life data were collected in 2024. Average relative humidity was 79%, average monthly rainfall was 3.53 cm, and average temperature was 21.8 C with maximum temperature of 33.4 C and low of 14.2 C. The 10 hybrids all had acceptable fitness at 500’ elevation. Some hybrids showed more fitness than others. Hybrid 602 had the highest overall average health (3.8) and highest total flower count. Hybrids 620 and 626 also showed excellent fitness as well as highest flower counts. While none of the hybrids are considered unfit for production in similar conditions, some did perform less well. Hybrid 88 and Hybrid 633 had the lowest average health at 3.0 followed closely by Hybrids 583 (3.2), 679 (3.3), and 563 (3.3). These varieties also had some of the lowest total flower counts. All of the hybrids in this study are considered potential candidates for release and continued trialing. Future work can include long term trialing of these plants, and trialing at different microclimates across the State.

Speakers

Poster presentation (individual talk), Floriculture

SUBJECT Floriculture

ASHS 2024 Conference

12:45pm HST

Orville Baldos

Christyn Wong

Lindsey Watanabe

Sherry Ann Hara

12:55pm HST

Sonja Maki

Zachary Endreas

1:05pm HST

Lilin Chen

Ping Yu

Yulong Chen

1:15pm HST

Yulong Chen

Lilin Chen

Ping Yu

1:25pm HST

Kristine Lang

Alexis Barnes

Ellen Fitzpatrick

Hannah Voye

1:35pm HST

James Klett

1:45pm HST

Orville Baldos

Hannah Lutgen

1:55pm HST

Russell Galanti

Alberto Ricordi

Kenneth Leonhardt