KC Gardens

A fertilization guide for vegetable gardens, which may need help after record rains

Vegetable gardens like need a boost of nutrients after record rainfall in May.
Vegetable gardens like need a boost of nutrients after record rainfall in May. The Wichita Eagle

How are your vegetables growing?

This has been a strange spring. Record May rainfall resulted in some area gardens lush with growth while others struggled with the excessive moisture.

The heavy rainfall leached nutrients from the soil essential for healthy root development. This means a little fertilizer may be just what the plants need for a productive season.

Nitrogen is the nutrient plants need most. Use a fertilizer composed primarily of nitrogen, such as nitrate of soda (16-0-0). Apply this fertilizer 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 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.

Only have a few plants and not a 100-foot row? Then use these rates.

When using the nitrate of soda, apply two tablespoons per plant. If using high-nitrogen lawn fertilizer, cut the application to one tablespoon per plant. Do not place in a clump in one spot. Evenly spread any fertilizer application out and around the planting. Just as the roots go out in all directions, so should the fertilizer.

What vegetables need food? The better question here is probably what vegetables do not need food.

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 are ready to fertilize.

Tomatoes require the most food. Three additional fertilizer applications should be made during the growing season. The first application should be made one to two weeks before the first tomato ripens.

For those of you who planted early, this first application should be made now. Dispense the second application about a month later, or two weeks after picking the first ripe tomato. Make the third application another month after the second.

Got cucumbers and melons? They will need a side dressing of fertilizer one week after blossoms begin. 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 because they develop their fruit soon after blooming. Feed your other vegetables in the next few weeks as well.

Peppers and eggplant should receive fertilizer after the first fruits began to set. Sweet corn requires two fertilizer applications — the first when plants are 8 to 10 inches tall and the second one week after tassels appear.

What about organic options? Organic sources of fertilizers can be used with great success. These products generally have a lower percentage of nitrogen, usually somewhere between 5% to 10%. Based on the lower amount of nutrient per pound, you will want to slightly increase the application rates from the nitrate of soda for adequate fertilization.

Timely fertilization helps ensure a summer filled with fresh garden vegetables. I am looking forward to picking vine ripe tomatoes all season long.

Dennis Patton is a horticulture agent with Kansas State University Research and Extension. Got a question for him or other university extension experts? Email them to garden.help@jocogov.org.

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