Many gardens already have sweet corn with at least 8 leaves. If your sweet corn has this many leaves it needs to be fertilized. For every 250 feet of row, scatter ½ pound of Nitrogen along the side of the row, carefully rake it in and water to move the nitrogen into the root zone.
The sweet corn in the photo is yellow due to a lack of nitrogen fertilizer. Applying nitrogen will help correct that problem.
If your cucurbits (squash, pumpkin, cucumber & melon plants) are vining as is seen in the photo, you should fertilize with 0.1 pounds of nitrogen per 250 foot of row in the same manner as I’ve described with corn.
One-tenth of a pound of Nitrogen and even one-half pound of nitrogen seems like an awfully small amount and it is but these small amounts are necessary to keep these plants growing properly so they will produce the quantity and quality of vegetable you expect to harvest.
One-tenth of a pound of nitrogen does not mean one-tenth of a pound of fertilizer. No fertilizer is 100% nitrogen. Fertilizers, whether synthetically manufactured or organic, contain varying levels of nitrogen. If you use ammonium sulfate as your nitrogen source, it contains ~20% N. Therefore 5 pounds of ammonium sulfate equals 1 pound of nitrogen. If you use Corn Gluten (~10% N) as your nitrogen source it will take 10 pounds of corn gluten for every pound of Nitrogen.
Depending on what you are using for fertilizer, calculate the amount of fertilizer needed based on its nitrogen content and fertilize. For more specifics on how much Nitrogen your vegetables need, check out the fact sheets at http://www.coopext.colostate.edu/TRA/PLANTS/Vegetable_Gardening_Nitrogen_Recommendations.pdf and http://www.coopext.colostate.edu/TRA/PLANTS/Organic_Fertilizers.pdf. These fact sheets provide more information on fertilizing your vegetable garden and the organic products available.
The above photos also show a drip irrigation system used to water these vegetables and shades on the west and south sides of the cucurbits. Both of these methods of production increase yield and the quality of your vegetables.
