{"id":780,"date":"2018-07-03T07:06:06","date_gmt":"2018-07-03T14:06:06","guid":{"rendered":"http:\/\/blogs.cdfa.ca.gov\/FREP\/?p=780"},"modified":"2019-03-13T14:41:50","modified_gmt":"2019-03-13T21:41:50","slug":"research-update-nitrogen-management-of-organic-leafy-green-vegetables-on-the-central-coast","status":"publish","type":"post","link":"https:\/\/blogs.cdfa.ca.gov\/FREP\/index.php\/research-update-nitrogen-management-of-organic-leafy-green-vegetables-on-the-central-coast\/","title":{"rendered":"Research Update: Nitrogen management of organic leafy green vegetables on the Central Coast"},"content":{"rendered":"<p><strong>Project Title:\u00a0<\/strong>\u201cEvaluation and demonstration of nitrogen management of organic vegetable production in leafy green vegetables on the Central Coast\u201d<\/p>\n<p><strong>Project Leaders:\u00a0<\/strong>Richard Smith, Michael Cahn, and Tim Hartz<\/p>\n<p><strong>Location:\u00a0<\/strong>California Central Coast<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" data-attachment-id=\"781\" data-permalink=\"https:\/\/blogs.cdfa.ca.gov\/FREP\/index.php\/research-update-nitrogen-management-of-organic-leafy-green-vegetables-on-the-central-coast\/p1010115\/\" data-orig-file=\"https:\/\/blogs.cdfa.ca.gov\/FREP\/wp-content\/uploads\/2018\/06\/P1010115.jpg\" data-orig-size=\"2048,1536\" data-comments-opened=\"1\" data-image-meta=\"{&quot;aperture&quot;:&quot;0&quot;,&quot;credit&quot;:&quot;&quot;,&quot;camera&quot;:&quot;&quot;,&quot;caption&quot;:&quot;&quot;,&quot;created_timestamp&quot;:&quot;0&quot;,&quot;copyright&quot;:&quot;&quot;,&quot;focal_length&quot;:&quot;0&quot;,&quot;iso&quot;:&quot;0&quot;,&quot;shutter_speed&quot;:&quot;0&quot;,&quot;title&quot;:&quot;&quot;,&quot;orientation&quot;:&quot;0&quot;}\" data-image-title=\"Leafy greens\" data-image-description=\"\" data-image-caption=\"\" data-medium-file=\"https:\/\/blogs.cdfa.ca.gov\/FREP\/wp-content\/uploads\/2018\/06\/P1010115-300x225.jpg\" data-large-file=\"https:\/\/blogs.cdfa.ca.gov\/FREP\/wp-content\/uploads\/2018\/06\/P1010115-1024x768.jpg\" class=\"alignright size-medium wp-image-781\" src=\"http:\/\/blogs.cdfa.ca.gov\/FREP\/wp-content\/uploads\/2018\/06\/P1010115-300x225.jpg\" alt=\"Lettuce in California Central Coast\" width=\"300\" height=\"225\" srcset=\"https:\/\/blogs.cdfa.ca.gov\/FREP\/wp-content\/uploads\/2018\/06\/P1010115-300x225.jpg 300w, https:\/\/blogs.cdfa.ca.gov\/FREP\/wp-content\/uploads\/2018\/06\/P1010115-150x113.jpg 150w, https:\/\/blogs.cdfa.ca.gov\/FREP\/wp-content\/uploads\/2018\/06\/P1010115-768x576.jpg 768w, https:\/\/blogs.cdfa.ca.gov\/FREP\/wp-content\/uploads\/2018\/06\/P1010115-1024x768.jpg 1024w, https:\/\/blogs.cdfa.ca.gov\/FREP\/wp-content\/uploads\/2018\/06\/P1010115.jpg 2048w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><strong>Overview:<\/strong>\u00a0This project aims to evaluate the proportion of crop nitrogen (N) that is provided by soil organic matter mineralization in organic leafy vegetable production under coastal climate conditions. This research also seeks to better understand the potential loading of N and phosphorus (P) in organic systems.<\/p>\n<p><strong>Issue:\u00a0<\/strong> Substantial research about the expected N mineralization of common organic fertilizers and amendments is available, but there are significant differences among research sources, which can contribute to grower uncertainty. Coupling this uncertainty with the difficulty of managing irrigation of shallow-rooted crops, and a rotational system in which multiple crops are grown annually, it is easy to see how diverse and potentially inefficient N fertility practices could arise. Given the high value of organic leafy vegetables, there is resistance to taking risks with reducing nitrogen applications to these crops. Organic vegetable production in the Central Coast is expanding, which intensifies the economic and environmental impacts of current fertility practices.<\/p>\n<p><strong>Impact:\u00a0<\/strong>This study provides a practical and easy-to-use method of estimating N mineralization from organic matter. This information will assist organic and conventional vegetable growers, who apply organic fertilizers, with fertilization scheduling, which will help to reduce N and P application rates without affecting yield.<\/p>\n<p><strong>Approach:<\/strong>\u00a0 The project leaders conducted trials on commercial organic fields in the Salinas Valley using two pelleted fertilizers (manure vs. non-manure based), to compare the effects of application method (surface application vs. shallow incorporation) on N mineralization. The fields included a cross section of organic producers, soil types and locations in the Salinas Valley. For this project, they determined the balance of inputs of N and P into the production fields and the removal of N and P in the harvested product. N and P inputs included fertilizer, mineral N in irrigation water, composts and crop residues.<\/p>\n<p><strong>Preliminary Results: <\/strong>The data from these trials indicated that the lag time in N mineralization from organic fertilizers is substantial. N mineralized from applied fertilizer ranged from 36-54% N released in the first crop cycle. Yield was much more closely correlated to the amount of residual soil N. Additionally, the researchers found that the organic field sites had P levels that were as high as conventionally managed fields, but values were not elevated beyond conventional fields despite higher annual applications of P.<\/p>\n<p>These studies underscore the complexity of fertilization for fast maturing, high N demanding, leafy green vegetables in an organic system. Over the two years of evaluations, researchers observed that significant amounts of fertilizer N remain in the fields, which contributes to a buildup of total N in the soil system, but the fate of this N is not well understood. Estimates of N mineralization from soil organic matter and initial soil nitrate levels are an essential tool in helping guide fertilization of organic leafy green vegetables.<\/p>\n<p><strong>What\u2019s next:<\/strong> The last year of this project will focus on integrating the mineralization data developed by this research with the algorithms currently used in <a href=\"https:\/\/v3.cropmanage.ucanr.edu\/Home\/SplashPage?ReturnUrl=%2F\">CropManage<\/a>. This integration of data will make the N management aspect of CropManage more applicable and useable for organic vegetable producers.<\/p>\n<p>Additionally, results from this project have been presented at seven events across the Central Coast over the past two years. There will be additional events in 2018 and a demonstration field day for this project will be held at the USDA Spence Research Station. Check the <a href=\"http:\/\/blogs.cdfa.ca.gov\/FREP\/?page_id=304&amp;ai1ec=\">FREP Calendar<\/a> to get updates on all upcoming field days and outreach events related to FREP\u2019s research and priorities.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Project Title:\u00a0\u201cEvaluation and demonstration of nitrogen management of organic vegetable production in leafy green vegetables on the Central Coast\u201d Project Leaders:\u00a0Richard Smith, Michael Cahn, and Tim Hartz Location:\u00a0California Central Coast Overview:\u00a0This project aims to evaluate the proportion of crop nitrogen (N) that is provided by soil organic matter mineralization in organic leafy vegetable production under coastal climate conditions. This research &hellip;<\/p>\n<div class=\"m-y-md text-right\"><a href=\"https:\/\/blogs.cdfa.ca.gov\/FREP\/index.php\/research-update-nitrogen-management-of-organic-leafy-green-vegetables-on-the-central-coast\/\" class=\"btn btn-primary\" aria-label=\"Continue reading the blog post...\">Read More<\/a><\/div>\n","protected":false},"author":9,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_EventAllDay":false,"_EventTimezone":"","_EventStartDate":"","_EventEndDate":"","_EventStartDateUTC":"","_EventEndDateUTC":"","_EventShowMap":false,"_EventShowMapLink":false,"_EventURL":"","_EventCost":"","_EventCostDescription":"","_EventCurrencySymbol":"","_EventCurrencyCode":"","_EventCurrencyPosition":"","_EventDateTimeSeparator":"","_EventTimeRangeSeparator":"","_EventOrganizerID":[],"_EventVenueID":[],"_OrganizerEmail":"","_OrganizerPhone":"","_OrganizerWebsite":"","_VenueAddress":"","_VenueCity":"","_VenueCountry":"","_VenueProvince":"","_VenueState":"","_VenueZip":"","_VenuePhone":"","_VenueURL":"","_VenueStateProvince":"","_VenueLat":"","_VenueLng":"","_VenueShowMap":false,"_VenueShowMapLink":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":false,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2}},"categories":[86],"tags":[194,58,207],"class_list":["post-780","post","type-post","status-publish","format-standard","hentry","category-all","tag-central-coast-agriculture","tag-nitrogen-management","tag-organic-amendments"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"jetpack_shortlink":"https:\/\/wp.me\/p9r16A-cA","jetpack-related-posts":[{"id":235,"url":"https:\/\/blogs.cdfa.ca.gov\/FREP\/index.php\/research-update-improving-n-use-efficiency-of-cool-season-vegetables-with-broccoli-rotations\/","url_meta":{"origin":780,"position":0},"title":"Research Update: Improving N Use Efficiency of Cool Season Vegetables with Broccoli Rotations","author":"Brooke Elliot","date":"July 1, 2017","format":false,"excerpt":"Research Project: Improving N Use Efficiency of Cool Season Vegetable Production Systems with Broccoli Rotations. Smith R. et al. Status: Completed Issue: The cool season vegetable production areas of the California\u2019s Central Coast frequently grow two or three crops during the growing season. The dominant crops\u2014like lettuce and spinach\u2014require high\u2026","rel":"","context":"In &quot;All&quot;","block_context":{"text":"All","link":"https:\/\/blogs.cdfa.ca.gov\/FREP\/index.php\/category\/all\/"},"img":{"alt_text":"photograph of a field of vegetables","src":"https:\/\/i0.wp.com\/blogs.cdfa.ca.gov\/FREP\/wp-content\/uploads\/2017\/05\/IMG_5337-300x199.jpg?resize=350%2C200","width":350,"height":200},"classes":[]},{"id":139,"url":"https:\/\/blogs.cdfa.ca.gov\/FREP\/index.php\/key-learnings-from-the-frepwpha-conference\/","url_meta":{"origin":780,"position":1},"title":"Key Learnings from the FREP\/WPHA Conference","author":"Brooke Elliot","date":"November 30, 2016","format":false,"excerpt":"The twenty fourth annual FREP\/WPHA Conference took place on October 26-27, where speakers from industry, academia, and agricultural consulting provided cutting edge information on nutrient management in California agriculture. The conference presentations covered a wide range of nutrient management topics including education and outreach, soil microbiology, government regulations and irrigation,\u2026","rel":"","context":"In &quot;Nutrient Management Events&quot;","block_context":{"text":"Nutrient Management Events","link":"https:\/\/blogs.cdfa.ca.gov\/FREP\/index.php\/category\/nutrient-management-events\/"},"img":{"alt_text":"Conf-Key-Learnings-Banner","src":"https:\/\/i0.wp.com\/blogs.cdfa.ca.gov\/FREP\/wp-content\/uploads\/2016\/11\/Conf-Key-Learnings-Banner-1024x330.jpg?resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/blogs.cdfa.ca.gov\/FREP\/wp-content\/uploads\/2016\/11\/Conf-Key-Learnings-Banner-1024x330.jpg?resize=350%2C200 1x, https:\/\/i0.wp.com\/blogs.cdfa.ca.gov\/FREP\/wp-content\/uploads\/2016\/11\/Conf-Key-Learnings-Banner-1024x330.jpg?resize=525%2C300 1.5x"},"classes":[]},{"id":1449,"url":"https:\/\/blogs.cdfa.ca.gov\/FREP\/index.php\/accepting-proposals-2020-frep-grants\/","url_meta":{"origin":780,"position":2},"title":"Now Accepting Proposals for 2020 Fertilizer Research and Education Program Grants","author":"Brooke Elliot","date":"December 5, 2019","format":false,"excerpt":"The California Department of Food and Agriculture\u2019s (CDFA) Fertilizer Research and Education Program (FREP) is now accepting proposals for the 2020 grant cycle. FREP\u2019s competitive grant program funds research and education to advance the efficient use of fertilizer materials and reduce environmental impacts associated with them. Two Requests for Proposals\u2026","rel":"","context":"In &quot;FREP Grant Program&quot;","block_context":{"text":"FREP Grant Program","link":"https:\/\/blogs.cdfa.ca.gov\/FREP\/index.php\/category\/frep-grant-program\/"},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":189,"url":"https:\/\/blogs.cdfa.ca.gov\/FREP\/index.php\/research-update-fertilizer-value-of-nitrogen-in-irrigation-water\/","url_meta":{"origin":780,"position":3},"title":"Research Update: Fertilizer Value of Nitrogen in Irrigation Water","author":"Brooke Elliot","date":"February 15, 2017","format":false,"excerpt":"Research Project: Determining the Fertilizer Value of Ambient Nitrogen in Irrigation Water - Cahn, M. et al. Status: Final year of study Issue: Irrigation water from many wells on the Central Coast contains a significant amount of nitrate-nitrogen (NO3-N). The N content in irrigation water has not been accounted for\u2026","rel":"","context":"In &quot;All&quot;","block_context":{"text":"All","link":"https:\/\/blogs.cdfa.ca.gov\/FREP\/index.php\/category\/all\/"},"img":{"alt_text":"Manifold and injection system used for simulating irrigation water with different concentrations of nitrate-N.","src":"https:\/\/i0.wp.com\/blogs.cdfa.ca.gov\/FREP\/wp-content\/uploads\/2016\/12\/Cahn-blog-300x200.jpg?resize=350%2C200","width":350,"height":200},"classes":[]},{"id":334,"url":"https:\/\/blogs.cdfa.ca.gov\/FREP\/index.php\/grants-to-begin-funding-january-2018\/","url_meta":{"origin":780,"position":4},"title":"Grants to Begin Funding January 2018","author":"Brooke Elliot","date":"January 2, 2018","format":false,"excerpt":"The Fertilizer Research and Education Program (FREP) of the California Department of Food and Agriculture (CDFA) is pleased to announce the award of almost $800,000 in grant funds to agricultural organizations and universities this year. These grants will fund four projects that will improve the efficiency and reduce the environmental\u2026","rel":"","context":"In &quot;FREP Grant Program&quot;","block_context":{"text":"FREP Grant Program","link":"https:\/\/blogs.cdfa.ca.gov\/FREP\/index.php\/category\/frep-grant-program\/"},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":72,"url":"https:\/\/blogs.cdfa.ca.gov\/FREP\/index.php\/cdfa-accepting-concept-proposals-for-2016-fertilizer-research-and-education-grants\/","url_meta":{"origin":780,"position":5},"title":"CDFA Accepting Concept Proposals for 2016 Fertilizer Research and Education Grants","author":"Brooke Elliot","date":"December 29, 2015","format":false,"excerpt":"The California Department of Food and Agriculture\u2019s Fertilizer Research and Education Program (FREP) is currently accepting concept proposals for the 2016 grant cycle. FREP\u2019s competitive grant program funds research that advances the agronomic and environmental performance of fertilizing materials. The 2016 Request for Proposals (RFP) includes several initiatives put forth\u2026","rel":"","context":"In &quot;FREP Grant Program&quot;","block_context":{"text":"FREP Grant Program","link":"https:\/\/blogs.cdfa.ca.gov\/FREP\/index.php\/category\/frep-grant-program\/"},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]}],"post_mailing_queue_ids":[],"_links":{"self":[{"href":"https:\/\/blogs.cdfa.ca.gov\/FREP\/index.php\/wp-json\/wp\/v2\/posts\/780","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blogs.cdfa.ca.gov\/FREP\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blogs.cdfa.ca.gov\/FREP\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blogs.cdfa.ca.gov\/FREP\/index.php\/wp-json\/wp\/v2\/users\/9"}],"replies":[{"embeddable":true,"href":"https:\/\/blogs.cdfa.ca.gov\/FREP\/index.php\/wp-json\/wp\/v2\/comments?post=780"}],"version-history":[{"count":6,"href":"https:\/\/blogs.cdfa.ca.gov\/FREP\/index.php\/wp-json\/wp\/v2\/posts\/780\/revisions"}],"predecessor-version":[{"id":804,"href":"https:\/\/blogs.cdfa.ca.gov\/FREP\/index.php\/wp-json\/wp\/v2\/posts\/780\/revisions\/804"}],"wp:attachment":[{"href":"https:\/\/blogs.cdfa.ca.gov\/FREP\/index.php\/wp-json\/wp\/v2\/media?parent=780"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blogs.cdfa.ca.gov\/FREP\/index.php\/wp-json\/wp\/v2\/categories?post=780"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blogs.cdfa.ca.gov\/FREP\/index.php\/wp-json\/wp\/v2\/tags?post=780"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}