Fertilizers contains the essential nutritional elements plants need to be healthy and grow. The soil naturally provides basic nutrients for plant growth, however, landscape plants need supplemental food to grow properly and resist insects and diseases. A basic soil test is recommended for all crops, lawns and gardens for understanding your fertilization needs. Instructions for taking soil samples and soil sample boxes are available at your county Extension office. (*Hamilton County Extension: 855-6113)
TRADITIONAL FERTILIZERS: On the packaging, fertilizer products will indicate how much nitrogen (N), phosphorus (P), potassium (K) and /or other minerals are in the product. A common garden fertilizer analysis is 6-12-12. Nitrogen helps build leaf and stem growth, Phosphorus helps the plant make strong root systems and Potassium helps growth of the entire plant, including making blooms.
Vegetable gardens require a “complete” fertilizer such as 6-12-12, 10-10-10 or 13-13-13 for proper growth and development. Manure is a complete fertilizer and may be used to supplement chemical fertilizer. Since most manure has less than 2 percent phosphate and less than 1 percent nitrogen and potash, several times more manure than chemical fertilizer must be applied if only manure is used.
HOMEMADE FERTILIZERS:
• Egg shells can be dried, crushed and sprinkle in your garden. They are made up of calcium carbonate, the main ingredient in agriculture lime.
• For acid loving plants, use 1 tablespoon white vinegar to 1 gallon water, apply every three months. Also coffee grounds can be used for acid loving plants such as azaleas, roses, rhododendrons and blueberries.
• Epsom salts can be used for roses, peppers, tomatoes and potatoes. Epsom salt is made up of magnesium and sulfate, which are vital plant nutrients. Use 1 gallon water to 1 tablespoon Epsom salt. Repeat once a month.
• Compost your yard, garden and food scraps to create a rich fertilizer that is teeming with beneficial microorganisms.
APPLICATION: If fertilizer is broadcast or applied in the rows, it should be worked into the soil before planting. Vegetable plants may be damaged by over-fertilization or fertilizer placed too near them. Greens and vegetables with a long growing season benefit from additional nitrogen during the growing season. This is “sidedressing”, keeping 4 to 6 inches away from the base of the plants. For tomatoes, peppers, and eggplant, start when the fruit is about the size of a half-dollar and repeat every four weeks through harvest. For cucumbers, cantaloupe, pumpkins, squash, and watermelon, sidedress when vines are 1 foot long and for sweet corn when six inches high.
ANNUAL FLOWERS: Annual flowers can use a balanced timed-release fertilizer according to package directions. This will feed plants for up to three months. Also used is 10-10-10 granular fertilizer, being careful not to drop any on the plants because it will burn them. Another alternative is to use a water soluble fertilizer- But, the effects of a water-based fertilizer do not last nearly as long as granular or timed-release fertilizers.
LAWNS: Lawns consist of cool season and warm season grasses. Cool season turf grass fescue needs to be fertilized in February and September according to package directions. Cool season lawns are not fertilized during the summer. For warm season turf of Bermuda and Zoysia fertilize in April and June. Apply the fertilizer when the lawn is dry and best before rain is forecast. There will be 30% less fertilizer needed by leaving grass clippings on the lawn.
PERENNIALS: Perennials and ornamental grasses should be fertilized when new growth appears in the spring. If you have not done so earlier, you may lightly apply organic fertilizer, such as milorganite around plants. Rotted manure is also good. Roses should be fertilized with a granular rose food after the first flush of blooms have faded and every 4-6 weeks through the blooming months, ending in September to help the bushes harden off for winter.
SHRUBS: Shrubbery should be fertilized now if you have not done so this spring with a granular fertilizer (10-10-10) according to package directions. To avoid burning, keep the fertilizer off the leaves or stems. Water the shrub after fertilizing. Azaleas, gardenias, and rhododendrons prefer an acid fertilizer.
TREES: The best time to fertilize trees extends from late fall, after the leaves have fallen, through the winter and into early spring before active new growth occurs. Fertilizer applied in the fall has a longer time period to penetrate the soil enabling the roots to more efficiently absorb it. In Tennessee, nitrogen fertilizers should not be applied to trees between August 1 and November 15. Trees that are rapidly growing should be fertilized yearly. Well-established, mature trees usually need to be fertilized once every three to four years. Fruit trees should be fertilized every year, including the year of planting. For established trees, apply fertilizers about one month prior to the start of growth in spring. Choose a high-nitrogen fertilizer such as 16-4-8. If available, a slow-release fertilizer is best.
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