Progress report for FW23-418
Project Information
Crop losses due to certain key pests like cucumber beetles, aphids, thrips, lepidoptera larvae, fusarium and more have been persistent problems in the organic cut flower industry. Currently, there is a minimal amount of readily available and regionally-specific information regarding sustainable Integrated Pest Management (IPM) practices for organic cut flower farms that are effective and economical. The question our research project is answering is what IPM methods are cost-effective for reducing losses due to key pests. This project is utilizing monitoring, data collection, and analysis; followed by implementation, further monitoring and data collection, and additional refinement as needed.
During the monitoring phase, we have identified key pests. During analysis, after identifying the highest pressure pests, establishing economic thresholds, and analyzing what the best sustainable management methods are, we have implemented those methods, and are continuing to monitor and record pest pressure and efficacy of the implementation utilized.
The significance of this project has been the development of research material on central coast pests on an organic cut flower farm that can and are being shared with the broader community, as well as decreasing pest pressure at Do Right Flower Farm. We have already disseminated existing research, tools and techniques for monitoring, project results, and IPM methodologies to the wider agricultural community through the Do Right Farm website, social media postings, the ASCFG newsletter and via two bilingual field days throughout the duration of the project. One in Spring and most recently this past winter. The final research report should help inform other growers in the region on successful methods to control key pests, ideally giving other producers better information and methods to improve yields and profits across all central coast organic flower productions. All educational and outreach materials will be provided in both English and Spanish.
Research:
- Identify key pests affecting a Central Coast CA organic cut flower farm.
- Research and determine cost-effective sustainable IPM methods for suppressing key pests.
- Reduce losses from key pests.
Education:
- Share research findings (research data, economic impact, implementation strategies) with local Central Coast growers and farm educators in English and Spanish.
- Share tools and methods for monitoring so that they can be reproducible on other farms.
We've put together a GANTT chart for the project which should be viewable here: Timeline - Sheet1 (2)
Cooperators
- - Technical Advisor
Research
Do Right Flower Farm is a two-acre certified organic cut flower farm located approximately one mile inland from the central Pacific coast. The farm is oriented north-south on flat land between wooded hillsides recently burned in the CZU Complex fire of 2020. The farm is adjacent to Waddell Creek, just inland from Rancho Del Oso Nature and History Center, and includes plant communities including coastal strand, coastal scrub, riparian, meadow, marsh, Monterey pine forest, mixed evergreen forest, chaparral and redwood forest.
The climate of the farm is tempered due to its position in this valley and sees annual high temperatures of approximately 75 degrees in the summer months and annual lows in the high-40s in the winter months. The farm does not receive frost. Annual rainfall is approximately 14 inches, most of it accruing in February. The farm is located in Sunset Zone 17.
The farm is made up of a propagation greenhouse, four high tunnels and approximately 3.5 acres of open-field production. The farm produces certified organic cut flowers for florists and wholesale and retail markets.
The objective of our study is to determine proactive and cost effective integrated pest management (IPM) methods to reduce losses from key pests at Do Right Flower Farm.
Data on pest severity and crop volume will be collected weekly using an established offline digital template in Google Sheets and all IPM methods used will be documented as they are implemented.
The first year of the project included weekly monitoring and recording of pest severity and crop volume, including IPM methods implemented. After the first full season (April-October) of monitoring, pest severity was analyzed and additional IPM techniques and economic thresholds were identified to implement in the second year of the project.
The second year of the project will include weekly monitoring of pest severity, crop volume and all IPM methods and economic thresholds implemented as a result of year one analysis. After the second full season (April-October) of monitoring, an analysis of the economic thresholds and IPM methods used will be conducted to determine the most effective IPM methods to reduce losses from key pests and maintain key pest pressure below thresholds.
The third year of the project will include weekly monitoring of the pest severity and crop volume using the most effective IPM methods determined from year one and two to reduce losses from key pests and maintain thresholds.
Weekly monitoring of pest severity is being captured in a Google Sheet spreadsheet and analyzed using Pivot Tables and graphs. A mobile phone is being used to capture the data in the offline Google Sheet and capture photos.
The annual analyses is being processed in Excel.
Materials used in the IPM methods are including various magnifying lenses, a phone-based camera, field knives, lab sample gathering tools (shovel, bags, markers, etc) and Google Sheets and Excel.
Comparison of IPM methods and resulting crop volume in years one, two, and three will determine whether our objective has been achieved.
We are measuring and evaluating: IPM methods implemented, volume from weekly projections numbers, losses from pests reported using weekly projections report, and pest severity levels using the weekly scouting report.
Using regular and consistent crop monitoring to identify pest severity early and implement proactive IPM techniques is allowing the grower to reduce losses from key pests and reduce costs from material applications and excessive labor. Establishing economic thresholds are allowing the grower to effectively implement IPM methods before pest pressure becomes economically damaging. Analyzing the yield and demand of crops throughout the season is allowing the grower to determine the cost-effectiveness of IPM techniques and prioritize the techniques used for the crops.
Research Outcomes
Cucumber Beetle in Dahlias
Cucumber beetle was identified as a key pest for this research after qualitative observations from years past. After finding that vacuuming was not a realistic use of time, blossom bagging sensitive varieties was the primary mechanical method to reduce damage. Quickly thrips filled the bags where they were protected from their natural predators pausing bagging as the primary control. Monitoring methods were adapted to include a weekly 10-flower sample count to track thrips activity in the dahlias. Once thrips pressure receded, blossom bagging commenced on sensitive varieties. While these bags did significantly reduce losses from cucumber beetle they were also very time consuming to apply and remove. On the farm, a wider mesh netting was used to protect chrysanthemums from cucumber beetle. It was found to not result in additional thrips infestation and with less time taken per bloom. For year two, the grower will invest in more of this netting to cover entire sensitive dahlia rows as an alternative to individual bagging.
A sunflower trap crop was planted in addition to sticky cards and lures as the biological method to reduce losses. Challenging weather at the start of the season delayed the timing of the sunflower trap crop. In year two, the grower will germinate the first two succession of sunflowers in the greenhouse and transplant to improve the trap crop's efficacy early in the growing season. The following succession will be direct sown, and lures will amplify the desirability of the sunflowers. In year one, after sticky cards were quickly filled, unfortunately also including beneficials, it was decided to halt their use. In year two, a weekly sweep of the sunflower trap crop for cucumber beetles will replace the sticky cards as a monitoring strategy.
In designing the project, the grower estimated that losses from cucumber beetles before this research were $3,340. At that time, no formal monitoring system was in place, so that number was pure estimation. After carefully tracking losses in year one of this research, the grower found that losses had surpassed that estimation well over twofold, coming in at $8,895. The reasons for this are likely a combination of estimating 2022 losses without monitoring and shifts in growing conditions after significant el niño winter storms. Findings from year two will be much more useful in identifying the reduction of losses from cucumber beetles from these chosen methods.
Fusarium in Lisianthus
The grower had experienced significant loss due to Fusarium in lisianthus before this research, but as a high-demand flower, it is appealing to research the potential for reducing those losses. In year one, cultural methods to increase drainage and airflow were implemented at the planting stage. Plugs were planted in tall beds with plugs planted high and reduced planting density from six inches to eight inches. A Trichoderma inoculant was intended to be used only at the plug stage but was added monthly through drip irrigation.
The much wetter than usual 2022-2023 winter in Central California delayed planting these plugs, leading to rootbound plants. Weekly rogue counts from rootbound plants were added to severity monitoring to better encapsulate the challenges Lisianthus faced in year one. Plants that did survive being rootbound were symptomatic of Fusarium despite these cultural and biological methods. Flowers were still sold selectively, but overall loss was still estimated at $568 due to fusarium. After loss from rootbound plants was estimated to be more than double that from fusarium ($1,256), it's fair to say that rootbound plants are another key pest of lisianthus to address in year two.
To better identify the feasibility of growing lisianthus organically in our location, irrigation water was tested for Fusarium. A negative result determined that the last change the grower will make to reduce loss from Fusarium in year two is planting in containers with clean media. Otherwise, the same preventative cultural methods used from the start will be implemented, along with the added monthly Trichoderma chemigation. To reduce loss from rootbound plugs, plants will be planted within a few days of receiving them.
Bacterial Blight in Zinnias
While zinnias had been a successful crop for the grower, bacterial blight was a primary cause of the premature end to their growing season. This caused it to be identified as a key pest of zinnias, and cultural and biological methods were identified to research. Like lisianthus, increasing drainage and airflow and a Trichoderma inoculant were the cultural and biological controls planned for year one. The grower would typically top zinnia beds with weed control fabric as they do with all annuals spaced at eight inches or wider. The lisianthus was never a good candidate for this fabric since most growers plant closely at around six inches. While the fabric is very helpful in controlling weeds on these long-blooming plants, it was not used. A negative effect of the fabric is that it hides the pooling of water underneath due to gopher damage to drip lines, which was hypothesized to increase the proliferation of blight. Zinnia plants were planted at a wider one-foot density, although there was some variation in how many rows per bed were used due to inconsistencies in the bed top dimensions. Plants were dipped in a Trichoderma inoculant before planting as planned, and additional monthly inoculant through the drip irrigation was added as well.
As the season progressed, another pest emerged: Sclerotinia. Weekly severity monitoring was coupled with rogue counts to quantify losses to either pest. This rogue counting also clarified that two-row beds experienced a significantly lower rate of loss from both Blight and Sclerotinia (86 plants loss from a combination of the two pests in two-row beds and 647 plants lost in three-row beds). For year two, all beds will be planted in two rows with one-foot spacing.
Before this research, the grower estimated that losses to Blight totaled $3,200. In the first year of research, losses to Blight were estimated at $171, and losses to Sclerotinia were estimated at $415.20. While it is true that a more accurate assessment of losses won't be possible until the end of year two, this trend is positive. Besides decreased planting density, weekly rogue counting and all other cultural methods will stay the same for year two of zinnia research. Biological methods will include the Trichoderma inoculant at planting and monthly and will likely be coupled with another biological inoculant to address Sclerotinia.
Education and Outreach
Participation Summary:
Research findings have been shared with two events. The first event was an on-farm event attended by 30+ other growers. Grower Kelly Brown and technical advisor Jessica Vaughan discussed the project in English and Spanish with the actual crops present for view and led an engaged discussion. The second event was held off the farm at nearby Cabrillo College Horticulture Department using a slides presentation. Fifty growers, including twenty-five of the ALBA (Agriculture and Land-based Training Association) students, attended with simultaneous translation into Spanish. Both events included handouts and follow-ups with information about monitoring techniques.
Kelly Brown and Jessica Vaughan co-authored an article for the Cut Flower Quarterly, a publication of the Association of Specialty Cut Flower Growers. This article will appear in the summer issue and will be followed up with annual articles updating readers on each year's research.
Research has also been shared through Instagram posts. With nearly 3,500 followers, many of whom are also flower growers, this is a helpful tool for connecting with growers at a distance.
Holding two events, one on farm and one off proved to be a convenient point of comparison in regards to what demographics are able to participate. The farm is located on the opposite side of the Santa Cruz County from the southeastern area more densely populated with a large Latino farm worker community. This hour drive may have been an important factor in less BIPOC representation at the on-farm event held in June 2023. The off-farm event in February 2024 on the other hand was held at Cabrillo College, a short fifteen minute drive from the primary agricultural area of Santa Cruz County, was half Spanish-speaking Latino farmers participating in the ALBA training program. The Cabrillo Horticulture Department coupled the event with a tour of their educational farm providing information about their classes. In this sense the event acted as a bridge between the ALBA students and further agricultural education available to them. Holding events both on and off the farm encouraged the research to reach a broader range of farmers, especially those Latino workers who have been traditionally excluded from educational settings while providing a majority of the farm labor.
Sharing research through the Cut Flower Quarterly will be reaching other English-speaking farm owners as the publication is shared to members of the Association of Specialty Cut Flower Growers. Through Instagram, posts are engaged with in English by other growers, owners or not. This forum is essentially a question and answer format with opportunity for crowdsourcing among other account holders.
Education and Outreach Outcomes
Research findings have been shared with two events. The first event was an on-farm event attended by 30+ other growers. Grower Kelly Brown and technical advisor Jessica Vaughan discussed the project in English and Spanish with the actual crops present for view and led an engaged discussion. The second event was held off the farm at nearby Cabrillo College Horticulture Department using a slides presentation. Fifty growers, including twenty-five of the ALBA (Agriculture and Land-based Training Association) students, attended with simultaneous translation into Spanish. Both events included handouts and follow-ups with information about monitoring techniques.
Kelly Brown and Jessica Vaughan co-authored an article for the Cut Flower Quarterly, a publication of the Association of Specialty Cut Flower Growers. This article will appear in the summer issue and will be followed up with annual articles updating readers on each year's research.
Research has also been shared through Instagram posts. With nearly 3,500 followers, many of whom are also flower growers, this is a helpful tool for connecting with growers at a distance.