Animals, fish, and birds all provide organic fertilizers that can help plants grow. Most animal-based fertilizers provide a lot of nitrogen, which plants need for leafy growth. Here are some of the most commonly available ones:

• Manures: Animal manures provide a lot of organic matter to the soil, but most have low nutrient value. A few, such as chicken manure, do have high available nitrogen content but should be used only composted because the fresh manure can burn the roots of tender seedlings.

• Bat/seabird guano: The poop from bats and seabirds, guano comes in powdered or pellet form and is actually high in nitrogen (10 to 12 percent). Bat guano provides only about 2 percent phosphorous and no potassium, but seabird guano contains 10 to 12 percent P, plus 2 percent K. The concentrated nitrogen in these products can burn young plants if not used carefully. Use them to make manure tea, as described later in this section. They tend to be more expensive than land-animal manures.

• Blood meal: It’s a bit gruesome, but blood meal is the powdered blood from slaughtered animals. It contains about 14 percent nitrogen and many micronutrients. Leafy, nitrogen-loving plants, such as lettuce, grow well with this fertilizer. It also reportedly repels deer, but may attract dogs and cats.

• Bone meal: A popular source of phosphorous (11 percent) and calcium (22 percent), bone meal is derived from animal or fish bones and commonly used in a powdered form on root crops and bulbs. It also contains 2 percent nitrogen and many micronutrients. It may attract rodents.

• Fish products: Fish byproducts make excellent fertilizers. You can buy them in several different forms. Fish emulsion is derived from fermented remains of fish. This liquid product can have a fishy smell (even the deodorized version), but it’s a great complete fertilizer (5-2-2) and adds trace elements to the soil. When mixed with water, it’s gentle, yet effective for stimulating the growth of young seedlings. Hydrolyzed fish powder has higher nitrogen content (12 percent) and is mixed with water and sprayed on plants. Fish meal is high in nitrogen and phosphorus and is applied to the soil. Some products blend fish with seaweed or kelp for added nutrition and growth stimulation.

You can use animal manures and compost to make liquid fertilizers called manure tea or compost tea The nutrients in these teas are readily available for plant use; the teas are gentle enough to use on young plants or spray on the plant foliage to give them a quick boost.

Here’s how to make manure or compost tea.

1. Place a shovelful of composted manure in a burlap or other porous cloth bag and secure the top.
2. Submerge the bag in about 10 to 15 gallons of water.
3. Let the liquid steep for one week or until the water takes on the color of brewed tea.  ....read more