By Hannah Moshay
While the majority of sunflowers in the U.S. are grown further north, in North Carolina sunflower has potential to fit well into many of our current row-crop rotations. Graduate student Abby Pleasant is working to identify key agronomic recommendations for organic high-oleic sunflower in North Carolina. This research includes a density study, nitrogen rate study, and a variety trial with two different planting dates. We are in the second year of a nitrogen rate study, investigating optimal rates of nitrogen for organic high-oleic sunflower.
Sunflower yield and oil quality is influenced by nitrogen availability. While too little nitrogen can stunt growth and limit yields, too much nitrogen can lead to issues including lodging and lower oil content. This nitrogen study includes different rates of a nitrogen fertilizer (0, 50, 100, 150, 200, and 250 lb N/ac) approved for use in organic production and two leguminous winter cover crops, crimson clover and hairy vetch. In late October and early November our team planted crimson clover and hairy vetch in Clinton, Kinston, and Oxford.
Earlier this spring, we terminated the crimson clover and hairy vetch using a flail mower and incorporated their residue into the soil. Sunflowers were then planted into these plots 1-2 weeks following termination and incorporation of these cover crops. We are interested in seeing whether these leguminous cover crops can provide sufficient nitrogen for good sunflower yields and their impact on oil quantity and quality.
We look forward to sharing more updates from the field this season!
Source : ncsu.edu