In the production of organic vegetables, nitrogen is important, yet can be quite costly to manage. Nitrogen management is even more challenging when production practices call for the use of polyethylene mulch combined with fertigation.The authors of a new study published in Hort Science have found that hydrolyzed fish fertilizer holds promise as an "economically feasible" nitrogen source for growing organic vegetables.
"Soluble organic nitrogen sources suitable for fertigation in organic vegetable production are much needed," said lead author of the study, Charles Ogles. Ogles and colleagues at Auburn University studied the effects of three different nitrogen sources during a 2-year crop sequence of yellow squash and collards. The scientists used hydrolyzed fish fertilizer, inorganic nitrogen (N) source with secondary and micro nutrients, inorganic nitrogen without secondary or micro nutrients, and a zero nitrogen control for the study. Nitrogen was applied at: recommended rates for both squash and collards, 80% of the recommended rates, and 60% of the recommended rates. The study design included a zero nitrogen treatment used as the control.