10 Natural Materials to Use as Organic Fertilizers

More and more people are going organic these days. From buying organic fruits and vegetables to gardening organically, many of us are trying to get away from using as many harmful chemicals as possible. In the garden, there are numerous natural materials that you can use to feed your plants. Following are ten different all-natural materials that you can easily find at most local gardening centers or which you may already have yourself. [Note: All application amounts are for a 100-square-foot area.]

Bloodmeal. Bloodmeal is just dried animal blood. It supplies 10% of the nitrogen needed. Application usually involves raking about 1-3 pounds into the surface of the soil where it will leach into the root areas. Bloodmeal usually lasts about 3-4 months. Another advantage is that it may repel rodents and even deer.

Bonemeal. Bonemeal is finely ground animal bones, usually that have been steamed. Its nutrient content is 11% phosphorus, 1% nitrogen, and 24% calcium; although, these percentages can vary. It is usually used, however, to put more phosphorus into the soil. Apply before planting and when the soil temperature is above 55 degrees Fahrenheit. Broadcast 1-3 pounds and then work into the top 6-12 inches of the soil.

Compost. Adding compost is one of the best things that you can do for your garden. It adds rich organic material that your plants will love. Add a layer (1-4 inches) in the spring and again in the fall and work into the soil. Also use it whenever you are creating new planting beds.

Fish emulsion. Fish emulsion contains 4% nitrogen, 1% phosphorus, and 3% potassium. It is usually sold as a liquid concentrate and needs to be diluted according to the instructions on the label. I also have a friend that gives me some from the pond that she has in her yard. (If you receive such a gift, it does not necessarily have to be diluted.) One thing that you should know is that fish emulsion does have a rather unpleasant odor.

Fish meal. Fish meal is dried, ground fish parts. Nutrients include 6% nitrogen, 3% phosphorus, and 3% potassium. You can use 1-3 pounds at the time of planting, depending upon how fertile your soil is. Usually fish meal lasts for one season.

Grass clippings. You do not have to go far to get these. Just mow your lawn and rake up some of the clippings. These are used to add organic matter to your garden. In your compost bin, they add a little nitrogen; although, the levels are rather negligible unless you add too much to your compost. Offset this by adding more "brown" matter, such as leaves. You can also add some extra soil to your compost.

Kelp (dry form). The nutrients in kelp are also negligible; although, it does contain 60 micronutrients and growth hormones for plants. It adds organic matter to the soil. Just apply one pound to the area.

Kelp (seaweed or liquid form). This contains the same nutrients as the dry form. During the growing period, dilute one-half teaspoon in one gallon of water. For leafy vegetables, either drench the soil or spray on the leaves every two weeks and every 3-4 weeks for your other plants.

Manure. The types of manure most frequently used are cow (2% nitrogen, 2% phosphorus, 2% potassium), horse (1.7% nitrogen, 0.7% phosphorus, 1.8% potassium), and poultry (4% nitrogen, 4% phosphorus, 3% nitrogen). Manure adds lots of organic matter to the soil; however, the high nitrogen levels, especially those found in poultry droppings, can burn plants. Dig the manure into the soil the season before you plan on planting in the area or add to your compost instead of applying directly to your plants. If applying to the soil, work 10-20 pounds of manure into the soil.

Worm castings. Worm castings do not have enough nutrients to even mention. What they do for the soil is add organic matter, and they also improve the structure of the soil. If your soil is low in organic matter, add 25 pounds of the worm castings. For soil that contains moderate amounts of organic matter, apply 10 pounds. Soil that has adequate organic matter only needs 5 pounds. Work into the soil.

The advantage that organic fertilizers have over inorganic fertilizers is that, except for manure, they can be used safely at any point during a plant's growth. Inorganic fertilizers are stronger and can actually burn plants if not applied with care. Use your organic fertilizers regularly -- in planting holes, around existing plants, and diluted as a spray for foliage. Your plants -- and the environment -- will thank you.

References:

Blume, James D., ed. New Garden Book. Des Moines, IA: Meredith Corporation, 1990.

Roth, Susan. New Complete Guide to Gardening. Des Moines, IA: Meredith Books, 1997.