Sunflower

  1. Lime, phosphate and potash can be broadcast over the soil surface in fall, winter or Nitrogen should only be applied in the spring at or near planting time.
  2. Reduce N rate by 60 to 80 pounds per acre following a well-established single-species winter cover crop of crimson clover or hairy vetch that has reached early bloom stage.
  3. Reduce N rate up to 20 pounds when following soybeans yielding 20 bu/acre or better.
  4. Double crop yield is generally about one-half of the initial seasons Apply 45 to 60 pounds of N per acre at establishment of a second season’s crop of sunflowers.
  5. On soils having a coarse textured subsoil, 10 pounds of sulfur per acre as part of the fertilizer blend may benefit yield, especially where deficiency symptoms have been observed in the past or where plant tissue tests have suggested sulfur deficiency.
  6. When boron tests less than 0.8 lbs/acre apply 1.0 lb of boron per acre annually. Follow up with another soil test in two (Note 6 is used only when the boron test indicates a need for boron.)