Delaware nutrient management certification for urban horticulture (2019)

Find out how YOU can get involved!
Hands-on experiential learning for UD undergrads!
Read our latest accomplishments!
Browse available resources.
Submit a sample today.
Analyses to help manage your land.
Chat with a DE Master Gardener.
You have questions. We have answers!
Contact UD Extension staff.
Protect your family, friends and community.
A person applying fertilizers to a lawn.
[ View as Infographic ]


Many of Delaware’s waters are impaired by excess amounts of nitrogen (N) and phosphorus (P), nutrients that come from non-point sources in agricultural and urban areas. From urban sources, these nutrients often stem from the use of fertilizers on lawns and landscapes. 

To mitigate this issue, urban horticulture professionals who fertilize more than 10 acres of land (i.e., private nutrient handlers) or apply nutrients for a fee (i.e., commercial nutrient handlers) must become nutrient certified as mandated in the 1999 Delaware Nutrient Management Act. In addition, the Delaware Nursery and Landscape Association requires Livable Lawns certified businesses to employ a certified nutrient handler.



University of Delaware Cooperative Extension offers initial nutrient management certification training to urban horticulture professionals as required by law. State-wide training sessions are led by UD Cooperative Extension, with oversight by the Delaware Nutrient Management Commission and the Delaware Department of Agriculture. In 2019, UD Cooperative Extension offered initial certification sessions and one examination session specifically for the urban horticulture audience.  



In 2019, twenty-one urban horticulture professionals attended the initial certification sessions for horticulture. Based on their certification pre- and post-examination, 15 of 18 tested and surveyed participants (83%) increased their knowledge of Delaware’s nutrient management issues and certification requirements. The average knowledge increase was 31% for those attending both sessions I and II. 

Evaluations were also conducted after each individual session. Here, respondents indicated they were responsible for nutrient management decisions on more than 1,257 acres of lawns and landscapes. Those surveyed also indicated they had gained skills as a result of attending the sessions. For example, 11 respondents (100%) indicating that they learned how to better interpret a soil test report. Willingness to adopt new or change existing management practices after attending the certification session was also measured using this survey: 6 respondents (55%) indicated that they would change how they manage turfgrass and 11 respondents (92%) indicated they would change the ornamental plants they recommend/plant for clients or their business. 

Ten individuals registered to take the Commercial Nutrient Handler examination, of which 7 (70%) passed and were certified as Commercial Nutrient Handlers with the Delaware Department of Agriculture. Eight additional individuals were newly certified as Private Nutrient Handlers. 



Funding to support the Delaware Nutrient Management Certification program is provided by the Delaware Nutrient Management Commission.