From Dennis Patton:
How are your vegetables growing? The rains have been plentiful which has made vegetable gardening pretty simple. But ample rainfall helps to leach nutrients from the soil which may leave our crop a little on the hungry side. Timely applications of fertilizers, especially nitrogen, are needed so the rapidly growing plants are not slowed down.
What fertilizer do they need?
Nitrogen is the nutrient that is most needed by our plants. Use a fertilizer composed primarily of nitrogen such as nitrate of soda (16-0-0). This fertilizer may be applied at the rate of 2 pounds (equals 2 pints) per 100 feet of row. High nitrogen lawn fertilizers such as a 27-3-3, 30-3-4, 29-5-4 or something similar are also good choices, but the rate should be 1 pound (1 pint) per 100 feet of row. Do not use lawn fertilizers that contain weed killers or weed preventers.
What vegetables need food?
The better question here is probably what vegetables do NOT need food? Yes, some vegetables will actually produce lower yields if they receive excessive amounts of nitrogen. These include sweet potatoes, watermelons, carrots, beets, parsnips and lettuce. Leave these crops alone when you get the fertilizer out.
Tomatoes require the most food. Three additional fertilizer applications should be made during the growing season. The first should be made one to two weeks before the first tomato ripens. For those of you that planted early, this first application should be made now. The second application should be about a month later, or two weeks after picking the first ripe tomato. The third application should be made another month after the second.
Got cucumbers and melons? They will need a side-dressing of fertilizer one week after blossoming begins. Three weeks later, add another side dressing of fertilizer to boost fruit production. Other vegetables that need fertilizing around bloom time are peas and beans since they develop their fruit soon after bloom.
A few more vegetables require food fairly soon. Peppers and eggplant should receive fertilizer after the first fruits began to set. Sweet corn requires two fertilizer applications. The first is when plants are 8 – 10 inches tall. The second is one week after tassels appear.
For more information, there is a publication on side-dressing that can be found at http://www.hfrr.ksu.edu/doc3952.ashx feed your vegetables so they feed you!