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Home HortTechnology Agricultural Educators, Organic Growers Benefit from Training Program
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UNIVERSITY PARK, PA—Professors Elsa Sánchez and Heather Karsten are passionate about helping organic farmers. The two faculty members from the Departments of Horticulture and Crop and Soil Sciences at Pennsylvania State University acknowledge the unique challenges facing organic growers, and designed a training program to help agricultural educators and growers with some complicated nutrient management issues.

In an article published in HortTechnology, the duo explained that nutrient management on organic farms can be challenging. "Typical organic nutrient management strategies include the use of compost, manures, other organic amendments, and green manures, which slowly release nutrients," Sánchez and Karsten noted. "Also, nutrient availability is often unpredictable with organic nutrient sources. This is particularly true of nitrogen (N), with first year availabilities ranging from less than 20% to more than 40%." These factors can lead to over-application of organic nutrient sources to ensure sufficient N for good crop yields, a practice that can result in excessive application of other nutrients and accumulation of salts in the soil. Organic farmers can face loss of profits due to the cost of over-applied nutrients, indirect losses from decreased yields, and pollution of surface and groundwater concerns.

To address these issues, Sánchez and Karsten first convened a focus group of organic vegetable growers to assess needs for information on using organic nutrient sources. Conversations with focus group participants revealed several key issues. "Organic growers often apply nutrients once every few years for a number of different crops grown in rotation, and they often have difficulty interpreting and/or using information provided by conventional soil and compost test analyses to apply organic nutrient sources," the report noted. "Additionally, the growers reported being challenged to find ways to meet crops' nitrogen needs with organic nutrient sources, and to use compost without accumulating excess salts and nutrients in the soil."

Following the focus group experience, the researchers and colleagues Tom Richard and Rick Stehouwer designed an intensive training program for agricultural educators in Pennsylvania, New York, and New Hampshire. Through a grant from the United States Department of Agriculture, National Institute of Food and Agriculture, Northeast Sustainable Agriculture Research and Education (NESARE) program, 14 educators were invited to participate in the year-long training program. Educators from university extension services, the Natural Resources Conservation Service, and the Rodale Institute in Pennsylvania and New Hampshire participated in three intensive training sessions. During the course of the year, participants developed soil and compost analysis recommendations for organic farms, evaluated three whole farm nutrient planning tools, created extension materials, and developed workshops intended for organic growers.

The results of the educator training program were found to be quite effective: subsequent educational workshops, presentations, and farm visits reached 714 growers, and publications developed during the training sessions have been used by more than 2575 people. "Participants in the training program rated their ability to help organic growers with nutrient management as 3.5 before the session, and 5.5 (on a 7-point scale, with 7 equaling 'excellent') after the sessions," the authors reported. "About a year later, all survey respondents rated their ability to help growers using organic nutrient sources as excellent or above average."

Organic growers who responded to a survey reported that their knowledge of using organic nutrient sources improved from 3.9 to 5.9 (on the 7-point scale) as a result of a workshop, and from 3.9 to 5.6 after a 1-day class developed by the training participants.

Karsten and Sánchez said that the multidisciplinary train-the-trainer approach they used in the program design was essential, noting that train-the-trainer model has the benefit of reaching many people with a low cost per person. "We found that the methodology used in this program allowed for expansion of individual and collective knowledge of a complicated topic, and development of high-impact, relevant, and effective educational programming for clientele."

The report includes recommendations for future training topics related to using organic nutrient sources that were proposed by program participants.


The complete study and abstract are available on the ASHS HortTechnology electronic journal web site:

Founded in 1903, the American Society for Horticultural Science (ASHS) is the largest organization dedicated to advancing all facets of horticultural research, education, and application. More information at


Original Article:

Development and Evaluation of a Training Program on Whole Farm Nutrient Planning for Organic Farms
Elsa S. Sánchez and Heather D. Karsten
HortTechnology 21:500–503. [Abstract][Full Text][PDF]

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