Organic Fertilizer

Organic Fertilizer -Garden design, Soil amendments

Organic Fertilizer

Organic Fertilizer | Choose the best organic fertilizers to suit you garden design needs. Learn the characteristics of each organic soil amendment.

Green Living Made Easy on Facebook
Bookmark and Share Subscribe Organic Fertilizer Selections

When used in reference to fertilizers, the word organic typically means a fertilizer that is derived from the decomposition or by-product of an organism. Inorganic means that the product is usually a petroleum by-product.

Organic Fertilizers can consist of Cottonseed meal, blood meal, fish emulsion, manure and sewage sludge.

Packaged fertilizers have their N-P-K values which stand for Nitrogen, Phosphorus and Potassium values stated on the package. Usually natural or organic fertilizers are high in only one of these three values.

Here is a listing of many commercially available organic fertilizer compounds:

Cottonseed Meal

Cottonseed Meal is a by-product of cotton manufacturing. It is somewhat acidic. Keep in mind that cotton crops are the most sprayed corps for controlling insects. It is advisable to compost Cottonseed meal for I year to reduce or eliminate the chemical levels.

Earthworm Castings

Earthworm Castings have a very high N-P-K rating and has many trace elements for a ideal soil amendment. It is made from earthworms that digest organic matter and excrete the castings.

Blood Meal

Blood Meal is dried, powdered blood from cattle slaughterhouses. It is very rich in N or nitrogen. It may burn plants if you are not careful.

Fish Emulsion

Fish Emulsion is a partially decomposed blend of pulverized fish, and is high in N or nitrogen.


Manure is a complete fertilizer, but has low amounts of nutrients. Common varieties are cow, pig, chicken and turkey. Be careful with fresh manures as they can easily burn plants, especially chicken and turkey manure.

Sewer Sludge

Sewer Sludge, commonly known as Milorganite, is the by-product of sewer and the product is manufactured in Milwaukee. The nutrient levels are 6-3-0 or as indicated on the packaging. It is a dry, granulated product and is long-lasting and burn resistant.

The use of this sewer sludge has some controversy in it's use around edible crops, as the long term use of this product does have some heavy metal content. I would not recommend it for the organic garden, but I would feel free to use if for lawns and flower beds.

Organic fertilizers contain relatively low nutrients when compared to the inorganic fertilizers, but they do increase the organic makeup of the soil and increase water-holding abilities of our soil and of coarse contribute nothing to the pollution of water tables, unless used nearby creek beds or ponds.

Corn Gluten

Corn Gluten is made from corn and is a natural pre-merge and fertilizer. If you plant garden seeds, don't use Corn Gluten until after the plants have matured. Then you can use it as both a fertilizer and a pre-merge to keep down weeds during the middle and later part of the year.

Read Green Living Made Easy's Review of Corn Gluten.

When you buy plantlets, go ahead and use the Corn Gluten as you will not have to worry about the pre-merge qualities with the established plantlets.

Bat Guano

Bat Guano, is made from bat excretions, very high in N or nitrogen and has a lot of trace minerals.

Alfalfa Meal

Alfalfa Meal, is a very good organic fertilizer which has a high vitamin and mineral content and N-K-P of 3-2-2. Good for roses, but is a good soil amendment for all plants. It can be added to a compost pile as well to breakdown carbon rich materials.

Rock Phosphate

Rock Phosphate, is used to boost phosphorus levels. NPK of 0-25-0 Will last a long time. This is an excellent source of phosphorus and will increase the root activity of your plants.


Potash is basically the by-product of wood ashes. It is high in potassium.

Bone Meal

Bone Meal, is dried blood that has a N or nitrogen value of about 13%. Bone Meal will not burn and is very slow release. Use it in the compost pile too.


Gypsum, is quite often used to sweeten acid soil such as clay and to provide better drainage in stiff clay soil. It is an excellent source of sulfur and calcium.

Coffee Grounds

Coffee Grounds, high in N or nitrogen and you should always dump your coffee grounds in your garden.

Soybean Meal

Soybean Meal, is high N or nitrogen with a value of N=7. It also has Phosphorus and some Potassium. Apply at the rate of 4 lbs/100 square feet.


Seaweed, has over 60 trace elements. This is usually combined with another fertilizer, such as fish emulsion to provide a balanced fertilizer for your garden.

With all of these organic fertilizers, as with most fertilizers, it is best to spread them around your plants and then work it into the soil very thoroughly so it works at the root zone of your plants.

Want to learn more about green living? Sign up for our Free Weekly Newsletter, and we'll deliver green living tips and information about high-quality green products to your inbox once a week. Rest assured that we'll never share your information with anyone and only use it to send you our free newsletter.