Performance of Nitrogen Liquid Fertilizer Solutions in Broccoli Used to Enhance Weed Control


Grower interest in nitrogen fertilizer sprays for weed control has raised questions about the relative effectiveness of various materials and the contribution these materials make toward the nitrogen nutrition of the crop. A research program established in 1988 evaluated weed control and crop response with four plantings of broccoli.

Assessment of Value of Aqueous Nitrogen Fertilizer Solutions as Fertilizer and Herbicide Supplement in Broccoli (1989)


Report to the Oregon Processed Vegetable Commission

Garvin Crabtree
Bill Mansour
OSU Dept of Horticulture


  1. Determine the potential selective herbicidal activity of three nitrogen-containing fertilizer solutions.
  2. Compare broccoli response to nitrogen applied in these foliar sprays to equal amounts of nitrogen applied in the usual form of side-dressed fertilizer.

Effect of Nitrogen Rate, Timing, Placement, and Catch Crops on Yield and Nitrogen Utilization in Vegetable Crops



  • To evaluate the effect of several rates of applied N, as affected by timing and method of placement, on the yield of broccoli.
  • To determine the time of maximum broccoli uptake of applied N.
  • To determine how much of the applied N remains in the soil as nitrate at harvest and following winter rainfall.
  • To evaluate the efficiency of a winter cover/catch crop in capturing residual nitrate N.