Development of disease management, fertility, and weed control best practices for northeast garlic production

Development of disease management, fertility, and weed control best practices for northeast garlic production

Summary

Garlic is a $20 million industry in New York, and it represents and important and growing niche crop across the Northeast. As the numbers of garlic growers and acreage in garlic have increased, the number of diseases associated with this once trouble-free crop have also increased. Nearly 25% of growers surveyed indicated they have lost 30% or more of their garlic crop at least once in the last five years.

To reduce these losses and increase productivity, we are developing best practices for garlic in the Northeast through a series of research trials. A post-harvest trial compares treatments by examining marketable yield and disease incidence following heated curing, cutting garlic tops and roots prior to curing, and washing immediately following harvesting. A weed control trial compares both organic and conventional options to determine which weed controls are the most efficient, effective, and feasible for organic and conventional growers. A fertility trial compares available recommendations from the Northeast to determine optimal timing and rates of fertilizers. These trials are replicated from the Albany, NY area down to Long Island, providing a diversity of soils, environmental conditions, and hardiness zones which will be applicable throughout the Northeast.

At this point all six post-harvest trials have been completed, yielding data which has helped growers understand the extent to which they can adjust temperature and the garlic plant itself to improve drying conditions. The two weed control trials have been completed and data have been compiled, but not yet analyzed. The three fertility trials have been completed and data have been analyzed, yielding information on minimum fertility needs but also demonstrating the need for additional research. 

Objectives/Performance Targets

Fertility trials: Each of the trials was successfully completed and data was collected during July. The data have helped us to clearly understand how much nitrogen should be applied as a minimum amount, but data on timing and higher rates were not as definitive. We installed an additional, unfunded fertility trial at the Geneva experiment station this fall to again look at this question with more replications and more careful weed control, since weed pressure was a significant factor at one site.

Nevertheless, we were able to share information with the growers about minimum rates of nitrogen that should be applied through our weekly newsletter and through interaction at the Saugerties garlic festival. The information will also be incorporated into the Cornell Guidelines Garlic Chapter, which is currently being completed.

Weed Control trials: The weed control trial was installed in the fall of 2012 and all applications were completed by the spring of 2013. Both trials suffered some adverse factors. The trial on Long Island was planted a week prior to Hurricane Sandy, which severely compacted the soil and may have washed some chemical products further through the soil than desired. The trial in the Hudson Valley suffered significant hail damage when plants had 5-7 leaves, which made assessing herbicide injury more difficult. Any damage from the hail was evenly distributed through the plots, however.

The data from this trial have not yet been analyzed. This task will happen prior to the Cornell Guidelines chapter being completed.

Post-harvest best practices: We had another warm, dry July, which facilitated drying in general. This year we were able to increase our average temperature to 110 degrees F in the drying tunnels, and we experimented with using dehumidifiers at night to reduce rehumidification of the garlic. The results of this year’s trials were consistent with the results from 2012, except that the sampling procedure used for the top cutting was changed to remove double-bulbs from the samples and increase uniformity of the starting bulb size. This change seems to have removed the weight changes noted in the top cutting lengths, as was hypothesized after 2012. This year, no differences were noted in cutting length and bulb weight.

• Herbicide trial plot plan LI
• Herbicide trial plan Hudson Valley
• Herbicide data LI
• Postharvest data 2013
• Postharvest protocol 2013
• Organic fertility trials protocol
• happy helper HV fertility trial
• HT drying example
• Shed drying example 2
• Shed drying example
• Herbicide trial drying HV
• Herbicide trial pictures
• Fertility data 2013

Accomplishments/Milestones

1) 1000 farmers receive 3 articles detailing research findings in the Veg Edge (450 subscribers) and The Garlic Press (600 subscribers in the Northeast). Winter ‘12-’13.

1 article and the research findings handout have been distributed through the VegEdge and the Garlic Press, respectively, reaching approximately 1050 people (2012). A second Garlic Press article is set for publication now, and two articles on post-harvest handling and fertility have been included in the Weekly Update, which reached over 1000 growers this year in our expanded 17-county region. One article on post-harvest handling was included in VegEdge in 2013. The same article was included in the New England Vegetable and Fruit Conference 2013 Proceedings.  

An additional article on weed control will be written and distributed to Veg Edge  and the Garlic Press this winter.

2) 250 farmers attend winter meetings and garlic schools to learn about fertility, weed control, and post-harvest care. 120 growers fill out surveys detailing their issues and responding to research information. Winters ‘12 and ‘13

Garlic schools were implemented in the early spring of 2013, in two locations in New York. 53 growers attended the session in Albany, which was rescheduled due to a snow storm. 35 people attended the garlic school at Geneva, NY. 

The post-harvest information was presented at NOFA, NY to an audience of approximately 100 growers. It was also presented to NOFA, VT to an audience of 45 growers. The EXPO allium session attracted an additional 46 growers. David Stern presented the post-harvest information at a MOFGA meeting as well. Attendance at this meeting is not known at this time. Most recently, the post-harvest information was presented at the NEVF Conference in Manchester, NH to approximately 100 growers. Final count from this meeting will be obtained for the final report.

We did not distribute surveys at the Organic Farming meetings, so fell short of our goal of 120 surveys. We only received 85 surveys. Additional surveying will occur this winter and at the end of the coming growing season.

3) 100 growers receive research trial information at the Saugerties Garlic Festival through CCE and the Garlic Seed Foundation. Well over 100 growers received information at Saugerties this year. Each grower received printed materials about our work, and growers who did not have their own booths visited our booth at Saugerties to gain information from the poster (attached).

4) 700 growers purchase Cornell Guidelines with new garlic chapter. 150 additional growers access garlic chapter online.

The chapter was again delayed, and will be completed and disseminated at the garlic schools in March 2014. At this point it will also be published online.

5) 30 growers receive more in-depth help implementing changes based on research findings from CCE educators or the Garlic Seed Foundation. Ongoing through project

20 growers have received in-depth help implementing changes so far, with many more receiving one-on-one consultation on a smaller scale.

• Garlic Poster Saugerties
• Postharvest handling presentation 2013 data
• Postharvest handling summary article 2013
• Postharvest handling presentation 2012 data

Impacts and Contributions/Outcomes

Growers have been especially excited by the post-harvest handling information which has become available. Many more growers are considering drying in high tunnels than in the past, and some have already successfully made the transition. Communication lines are becoming clearer, and more growers are aware of the research happening with garlic every day. We are looking forward to quantifying the changes in drying, fertility management, and weed control that we are hearing growers talk about on an increasing basis. 

Collaborators: