Fertilize with Manure without Damaging Plants
Fertilize with Manure
Manure is one of the best additions for your garden. It improves soil and fertilizes your plants by helping them to absorb water, oxygen and other nutrients, which are essential for their health. Other benefits of manure are that it's inexpensive, readily available and easy to mix into your garden soil.
Fertilizer and Amendment
Manure is both a fertilizer and a soil amendment (material added to improve soil). Manure slowly releases nutrients into the soil that plants can easily absorb. Manure contains nitrogen, phosphorus, potassium and micronutrients, which are important for plant health. Nitrogen is the most important nutrient that plants need and is responsible for rapid plant growth and the green color of plants.
Fresh manure has a very strong odor and is harmful to plants because it contains high levels of nitrogen and ammonia that can "burn" plants. Plants in contact with fresh manure will rapidly dehydrate, causing the leaves to turn brown and wither. This process is called burning.
Before manure can be used to fertilize plants, it must go through an aging process called composting. In this process, fresh manure sits for 3 to 12 months. As the manure ages, nitrogen changes into a form that won't burn plants, and any pathogens present in the manure are also killed. Another benefit from composting manure is that it loses its odor. (That's a big benefit!)
Cow manure is the most popular source of manure for plants because it doesn't contain high amounts of nitrogen and is less likely to burn plants. Other sources of manure for the garden are horses, chickens and rabbits. Based on the type of animal, manure has different levels of nitrogen. Rabbit manure has the highest level of nitrogen, followed by chicken, horse and cow manure, which has the lowest amount.
How to Apply Manure
To apply manure, add a 2 to 3 in. layer of manure on top of existing soil and mix in well. Like cow manure, horse, chicken and rabbit manure are great for your garden, but because they have higher levels of nitrogen, make sure that they are not fresh and that they have been composted. Do not use manure from cats, dogs or pigs, which contains dangerous pathogens.
Fresh manure can be added directly to soil as long as there aren't any growing plants. Mix the fresh manure with the existing soil in fall and don't add plants until spring arrives. By then, the manure will have aged long enough so it won't burn plants. It is especially important not to apply fresh manure during the growing season to vegetable gardens, because the pathogens found in fresh manure can contaminate vegetables.
Adding manure to your garden is a great way to fertilize your plants and improve the soil. Just be sure that the manure has been composted—keep in mind that "older is better" when adding manure to your garden.