LAWN CARE, LANDSCAPING AND GARDENING
FERTILIZERS Serious water problems result from applying synthetic fertilizers to lawns, gardens and agricultural fields.
Plants can only utilize a certain percentage of what you apply, and the excess fertilizer washes away with the rain into neighborhood waterbodies. Fertilizers contain nitrogen and phosphorus which end up feeding our streams and bays in addition to our lawns and gardens. These nutrients suffocate creeks, ponds, streams and rivers, and kill the fish that live in them. All told, the balance of nature is thrown off -- with disastrous consequences!
The excess fertilizer that's not washed away percolates down into the groundwater. Nitrate concentrations can build up, contaminate drinking wells, and seriously threaten human health.
Over fertilization can damage roots, cause excessive top growth, burn lawns, and lead to water pollution problems.
Other problems related to intensely applying fertilizer include the depletion of the soil's growing capacity, the accumulation of inorganic chemical residues in the soil, a decline in humus (the organic part of the soil made up of partially decomposed plant and animal material) and soil deterioration leading to "hardpan." Over fertilization also harms beneficial soil microorganisms and increases your garden's susceptibility to disease.
Fertilize wisely:
- Feed the soil, not the plant. Concentrate on building your garden's soil.
- Consider home composting. Compost is organic fertilizer made by mixing organic materials, such as kitchen scraps (no meats, bones, dairy products, or fats) and non-woody yard wastes with topsoil, manure, fish scraps, and biodegradable paper. Composting can be as simple as building a heap of at least 3 x 3 x 3 feet in a corner of the yard, or as complex as a series of turning units or a barrel composter which tumbles the waste for aeration.
Benefits are a continual source of organic materials for mulch on soil surfaces or for soil amendments incorporated into the soil and recycling as a sound alternative to needless landfill disposal.
To speed up composting, cut or shred wastes and achieve a good carbon to nitrogen ratio by mixing wastes high in carbon (paper, straw, leaves, wood chips, saw dust) with wastes high in nitrogen (food scraps, grass cuttings, manure), provide adequate moisture (damp sponge consistency), and adequate aeration (sufficient air passages) throughout the pile. Turning on a weekly basis can prevent the pile from being smothered so that bad odors don't develop.
- Know what your soil requires before applying any fertilizer. Don't fertilize if it isn't necessary. Monitor soil fertility by testing soil on a regular basis.
- Select a fertilizer that has little or no phosphorus and approximately 60% of the nitrogen in slow-release, water-insoluble form. Read labels carefully. Be wary of words such as "natural" and "organic." Some organic fertilizers contain too much phosphorus for safe water.
- Fertilize during dry seasons.
- Avoid applying fertilizer on windy days, prior to a forecast of heavy rains, or near paved surfaces. If you spill fertilizer on walks, patios, or driveways, sweep it up so it doesn't wash off in the next rain. Never apply fertilizer within 50 feet of a waterbody.
- Use fertilizer appropriately according to package instructions. Never use fertilizer formulated specifically for gardens on the lawn or vice versa. Generally fertilizer should be applied when the soil is moist. Watering lightly will help it sink into the root zone where plants can use it. Fertilizer that remains at the surface may be lost to rain or wind.
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