The following is in no way intended to be the last word on the chemical-vs-organic debate, but rather a basic outline describing the pros and cons of each.



If you were to ask 100 people for their opinions on this subject, you might well receive a hundred different points of view.

In my humble opinion, if used properly, both chemical and organic fertilizers can be safe. However, if used improperly, both can be, without question, unsafe.

Chemical Fertilizers

In very basic and general terms, a chemical fertilizer is a compound (collection of ingredients) that has been chemically processed or refined to increase its potency.

The introduction of chemical fertilizers in the early to mid 20th century is in many ways responsible for the massive increase in food an individual farmer can produce.

The main problem is the result of applying too much or an over-application of this class of fertilizers. Any plant (wheat, corn, etc.), can only use so much food during its growth cycle.

What's left over tends to travel into groundwater, streams, lakes and the ocean, due to rain or irrigation. This pollutes the natural environment and has caused a great number of problems.

More recently most farmers and fertilizer manufacturers are well aware of these problems and work hard to use this class of fertilizers responsibly.

The home gardener needs to be aware and use any chemical in a responsible manner as well. This is one instance where “too little” is much better than “too much.”

Organic Fertilizers

The organic class of fertilizers (again, in very basic terms) tends to be less refined and involve little or no chemical processing. Also, the natural environment tends to have an easier time of breaking down and absorbing them. However, a few types can and do pollute ground water and other water systems.

Animal manure (cow, chicken) can cause many problems if used improperly. Manure is a highly concentrated source of nitrogen, which is easily released when exposed to rain or other forms of irrigation.

Excess nitrogen and phosphorous have proven to be major problems when released into our waterways and other water sources.

One benefit of using an organic "fert" is an increase in the biological activities in the soil.

Micro-organism's within the soil help plants convert nutrients into food and help to break down old plant material which adds to the over all health of the soil and garden. Chemical products in general do not offer this benefit which is one of the complaints from the proponents of organic style gardening.

Chemical fert's have been popular for a long time, though because of over-application have caused many problems. However, if used correctly, they have also proven to be beneficial and safe for food crop production.

With the rise in popularity of organic style gardening there is a risk of misusing this class of fertilizer as well. To say that an organic product is completely safe and leave it at that is to not really understand the question of fertilizers in general.

I strongly recommend learning more about the chemical vs organic issue, and deciding for yourself which type is best suited for your needs.

For more information on both organic and chemical fertilizers, please visit:

The International Fertilizer Industry Association at: http://www.fertilizer.org

The University of Arizona at: http://www.ag.arizona.edu/gardening///fertilizer.html

A Word on Plant Nutrients

Most garden centers will have a huge array of fertilizers to choose from and all will have numbers on the packaging such as 4-10-5 or 15-15-15.

A very simple and accurate way to understand the meaning of those numbers is to remember, leaf-flower-root.

For example, a 4-10-5 fertilizer indicates good leaves – big/many flowers or fruit – good roots. 4-10-5 = leaf-flower-root.

Think of “10” as being the middle ground on a scale of one to twenty, one being the lowest, 20 being the highest. A set of equal numbers such as 10-10-10 or 5-5-5 indicates an all-purpose plant food and as the name implies should work well with most plants.

Always follow the directions for application of any gardening product and remember that too much fertilizer can ultimately burn part or all of your plants.

Tip: Length times Width will provide your total square footage for a planting bed. Example: 10 feet x 3 feet = 30 square feet.

Most garden centers or nurseries will be happy to answer any questions you may have and will assist you in obtaining the right type and amount of fertilizer or other garden additives.

Good Luck and Happy Gardening!