Soil test and fertilize.
“Do your soil tests and make sure you have 60 to 80 pounds of nitrogen available,” Young says. “But push your sunflowers to go deeper. Because sunflower roots go so deep, we’re finding we’re using moisture and nutrients that got away from other crops.”
Plant so sunflower don’t bloom during the heat of the summer.
“We try to have all the sunflowers in by June 20,” Young says. “That allows us to avoid having sunflowers pollinate during the hottest part of August. If we have five days of 100+ degree F heat in August, sunflower blooms won’t handle that.”
Young rotates glyphosate and other products for his pre-plant burndown of emerged weeds. He also applies Spartan pre-plant to provide residual control. Young looks for ways to manage the rotation to help control weeds in sunflowers. “We realized that cheatgrass was getting a head start because of our late planting strategy. Now we do a cheatgrass burndown in April, once snowmelt is gone. Clean corn helps set up clean sunflowers, too.”
Scout fields for insects and control pests that reach economic threshold levels.
“Scout your fields for insects rather than just scheduling spraying,” Young says. “You’re killing beneficial insects along with the pests, so use sprays carefully.”
Consider cover crops.
Some growers are concerned about low residue from sunflowers following corn. Young plants spring wheat and winter wheat behind sunflowers. Residue may be a little skimpy, but Young expects cover crops to help remedy that.
“Manage sunflowers like a crop, not like a scavenger,” Young says. “We’ve been rethinking our entire crop management process. Sunflowers are one of the best cash crops going.”
(Source – http://farmprogress.com/story-top-5-tips-sunflower-success-9-95761)