Does composted cow manure have weed seeds

Cow Dung Fertilizer: Learn The Benefits Of Cow Manure Compost

The use of cattle manure, or cow dung, in the garden is a popular practice in many rural areas. This type of manure is not as rich in nitrogen as many other types; however, the high ammonia levels can burn plants when the fresh manure is directly applied. Composted cow manure, on the other hand, can provide numerous benefits to the garden.

What is Cow Manure Made Up Of?

Cattle manure is basically made up of digested grass and grain. Cow dung is high in organic materials and rich in nutrients. It contains about 3 percent nitrogen, 2 percent phosphorus, and 1 percent potassium (3-2-1 NPK).

In addition, cow manure contains high levels of ammonia and potentially dangerous pathogens. For this reason, it’s usually recommended that it be aged or composted prior to its use as cow manure fertilizer.

Benefits Cow Manure Compost

Composting cow manure has several benefits. In addition to eliminating harmful ammonia gas and pathogens (like E. coli), as well as weed seeds, composted cow manure will add generous amounts of organic matter to your soil. By mixing this compost into the soil, you can improve its moisture-holding capacity. This allows you to water less frequently, as the roots of plants can use the additional water and nutrients when needed. Additionally, it will improve aeration, helping to break up compacted soils.

Composted cow manure also contains beneficial bacteria, which convert nutrients into easily accessible forms so they can be slowly released without burning tender plant roots. Composting cow manure also produces about a third less greenhouse gases, making it environmentally friendly.

Composting Cow Manure

Composted cow manure fertilizer makes an excellent growing medium for garden plants. When turned into compost and fed to plants and vegetables, cow manure becomes a nutrient-rich fertilizer. It can be mixed into the soil or used as top dressing. Most composting bins or piles are located within easy reach of the garden.

Heavy manures, like that of cows, should be mixed with lighter materials, such as straw or hay, in addition to the usual organic substances from vegetable matter, garden debris, etc. Small amounts of lime or ash may also be added.

An important consideration when composting cow manure is the size of your

or pile. If it’s too small, it won’t provide enough heat, which is essential for the composting process. Too big, however, and the pile may not get enough air. Therefore, frequently turning the pile is necessary.

Composted cattle manure adds significant amounts of organic material to the soil. With the addition of cow manure fertilizer, you can improve the overall health of your soil and produce healthy, vigorous plants.

How to Kill Weed Seeds in Cow Manure

Although cow manure is an excellent source of nitrogen and nutrients for the soil, it is also a source of weed seeds and pathogens, such as Escherichia coli and salmonella. Composting the manure in a hot compost pile kills both the weed seeds and bacteria, making it safe for use in the garden. Despite its being thoroughly decomposed, however, you should always wash your hands carefully after handling any compost or composting materials.

Building a Compost Pile

A hot compost pile is composed of 2- to 3-inch layers of high-nitrogen green and brown materials. High-nitrogen materials include raw manure; white clover (Trifolium repens, USDA zones 3 through 10) and the foliage of other legumes, such as peas (Pisum sativum). Green materials include fresh grass clippings, coffee grounds and kitchen scraps. Brown materials include dead leaves, garden debris, sawdust, shredded paper and straw. Layer the materials so the pile consists of approximately 25 percent high-nitrogen, 45 percent green and 30 percent brown or woody materials. Your compost pile should measure at least 3 feet square by 3 feet tall to maximize the heating effects of the decomposing materials.

Cooking the Compost

The compost pile should be moist, but not soaking wet, to start the decomposition process. Monitor the pile, measuring the internal temperature daily with a long-stemmed thermometer. When the pile reaches 155 degrees Fahrenheit, turn it to mix the ingredients and then allow it to heat up again. Mix the pile with a shovel or pitchfork whenever the temperature reaches 155 degrees Fahrenheit. Most weed seeds and pathogens die at 135 degrees Fahrenheit.

Cooling Down

When most of the organic materials in the compost pile have decomposed, the pile will start cooling down. If it starts cooling too soon, such as within the first two weeks, sprinkle it with water to moisten the ingredients and encourage the beneficial bacteria to continue the decomposition process. After six to eight weeks, the interior of the pile will be cool or barely warm. The finished compost should be dark and crumbly, resembling rich, loamy soil. Place a tarp over the pile to prevent windblown weed seeds from contaminating the new compost.

Using the Finished Compost

The fully decomposed manure is used directly on existing flower and vegetable gardens, dug into the soil before the growing season begins, and mixed with perlite and garden soil for planters and raised beds. Although the weed seeds and pathogens in the compost are dead, garden soil also contains weed seeds. As you dig the compost into the soil, the weed seeds are exposed to warmth and moisture, the two main requirements for sprouting. Thus, while you’ve killed the weed seeds in the manure, the garden may still sprout new weeds.

  • Extension: Composting to Reduce Weed Seeds and Plant Pathogens
  • Fine Gardening: Brewing Compost Tea
  • Oregon State University Extension Service: Turn Manure Into Compost for Your Garden
  • Oregon State University Extension Service: How to Encourage a Hot Compost Pile
  • University of Massachusetts Extension: Peas
  • Missouri Botanical Garden: Trifolium Repens

With degrees in fine and commercial art and Spanish, Ruth de Jauregui is an old-school graphic artist, book designer and published author. De Jauregui authored 50 Fabulous Tomatoes for Your Garden, available as an ebook. She enthusiastically pursues creative and community interests, including gardening, home improvement and social issues.