by Catherine Duffy

Created on: July 11, 2010

Manure is an organic substance that, when added to soil, allows plants to reach their full potential, by providing a controlled balance of nitrogen, phosphorous, and potassium. Providing a controlled balance is key. Before adding any amendment to soil it is essential for the gardener to know their soil's nutrient balance and needs. Over-application of fertilizers, to include manure, can lead to “burnt” soil, crop disturbance and even water pollution.

Soil Tests And Application

Soil testing kits can be purchased at hardware stores and garden centers. These tests will give you an overview of your soil's condition, its pH balance and the amounts of existing macro-nutrients. Test different areas of your garden as soil conditions are not often uniform throughout.

For precise soil conditions take a soil sample and send it to a testing agency. If your garden in is in the United States then your county's Master Gardener University Extension usually tests soil or has access to a list of certified testing agencies. In other areas, check with your local botanical gardens or university agricultural program.

Based on the results of these tests you can determine what amendments are needed to maximize your garden's growing conditions.

Types And Sources

Cow and horse manure are normally used in flower gardens. Chicken, horse and cow manures are generally used in vegetable gardens and for root crops. Rabbit, bat, alpaca and turkey manure are also used. Most gardeners choose their manure source based upon availability.

Consider your manure's source. Fresh manure from commercially raised chickens and cows can contain hormones and bacteria, such as E. coli. Use fresh manure in ornamental, not edible, gardens. Aged manure can safely be used in vegetable gardens. Simply add manure to compost. During the process of decomposition compost reaches temperature of 140 degrees Fahrenheit. After five days of 140-degree heat pathogens will die off. Cure the compost for an additional three to five months and the danger of deadly pathogens is significantly reduced.

Amount and Storage

Generally, the amount of manure used in your garden should not exceed 20 pounds per 100 square feet, when using chicken manure and no more than 30 pounds/square foot for cattle manure. Incorporate fresh manure into your garden in the fall. This allows the manure to age in the soil. Fresh manure kills seeds and burns young roots.

Choose an enclosed area for manure aging and storing. Large piles of manure left out in the open during winter snows and rain will leach nitrogen and phosphorous into soil and water. Excess nitrogen pollutes streams and rivers. Phosphorous causes algae blooms in standing water such as ponds as lakes.

When used responsibly manure benefits soil and crops. Manage manure and grow some bumper crops.

SOURCES:

Washington State University Learning Extension

http://www.extension.org/faq/1254

Colorado State University Learning Extension Manure

Manure For Your Garden

http://www.gardenersnet.com/atoz/manure.htm

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