Guest post written by Stephanie Suesan Smith, Ph.D., Information Central

Organic gardening involves a dance with nature, more so than any other type of gardening.  On the one hand, the gardener tries to grow things in harmony with nature.  This involves allowing some insects to eat your plants so that the beneficial insects have food.  It means you rotate crops, practice soil conservation techniques, choose cultivars that are adapted to your area and resistant to the pests, diseases, and other problems there, and only then, as last resort, do you use something to kill the bugs on your plants.  After all, you have to eat too.

Once it becomes apparent that the plants need some help, you have to decide what to put on them to do that.  Synthetics are out, with a few exemptions.  That is, if you adhere to the USDA organic standards.  Some states have stricter standards, and there are private certifiers that also have stricter standards.  Oregon Tilth is the strictest of these.  However, this article will deal with USDA standards.

Most people think natural substances are allowed in organic gardening.  There are some natural substances, however, that are so poisonous, or stay in the soil so long, that they are banned as well.  The list is actually pretty short, but somewhat scary.  Ash from manure burning, arsenic, lead salts, sodium fluoaluminate, strychnine, and tobacco dust are absolutely banned.  Calcium chloride, potassium chloride, and sodium nitrate are banned with a few exceptions.

Some of these are obvious – arsenic, strychnine, lead, sodium fluoaluminate –and some not so much.  The problem with manure that has not been composted in a hot compost pile for at least six months is that the animal may be fed a medicine or chemical, excrete some, and then when the manure is burned the chemical becomes something else that is harmful.  Calcium chloride and potassium chloride build up chloride in the soil, which is a toxin.  Sodium nitrate blows up.

Tobacco dust contains nicotine, which is very toxic to pretty much everything.  The old timers in my part of the country would use the spit from their chewing tobacco to kill grasshoppers.  It does, but it kills everything else, too.  So do not do that.

One caution is be aware of the contents of any manure, fertilizer, or soil you add to your fields before you spread it.  Commercial chicken farms feed their chickens arsenic to make them eat more so they gain weight faster.  The farms used to give away the manure and shavings the chickens left behind when they went to slaughter.  A fellow got some, spread it on his field, tilled it in good, then did a soil test.  It came back with really high levels of arsenic.  The state pulled his organic certification over it, which meant he had to wait three years and apply all over again to be an organic producer.  Ask for a copy of the soil test for any of that stuff before you buy it.  A reputable place will be more than happy to provide that.  If someone refuses, run the other way.

Stephanie Suesan Smith can be found at Information Central. You can find additional gardening posts there.  She is also a freelance writer and photographer with twenty years of experience writing academic and consumer articles.  Stephanie Suesan Smith lives in Hunt County, Texas with two dogs on 14 acres and is a master gardener.  She also does woodworking and has a Ph.D. in clinical psychology.

Related posts:

1. Organic Gardening: Beginners Guide to Growing Your Own Organic Vegetables Reviews Organic Gardening: Beginners Guide to Growing Your Own Organic...