Microorganisms are TINY life forms.
Bacteria, fungi, algae, protozoa, and other microscopic critters (microbes) are all microorganisms found in soil. The jury is still out on whether viruses are alive or not - but they are considered a microbe. According to Principles and Applications of Soil Microbiology (1998), you will find this many microorganisms in one gram of soil [1/5 the weight of an American nickel]:
• 100,000,000 - 1,000,000,000 bacteria
• 100,000 - 1,000,000 fungi
• 1,000 - 1,000,000 algae
• 1,000 - 100,000 protozoa
Try wrapping your brain around THOSE numbers! They must be having one heck of a party down there…
Some microorganisms can damage or kill plants. Bacteria can cause fireblight, cankers and soft rot. Fungal diseases include powdery mildew, Eutypa Dieback and rust. Viruses can cause Tomato Spotted Wilt, Cucumber Mosaic and many more.
Other microorganisms are critical to soil health because they make nutrients available to plants through the Nitrogen Cycle. Plants also exchange carbon, created through photosynthesis, for mineral nutrients from soil microbes. Other microbes stimulate plant immune systems and reduce stress to plants.
One soil microorganism in particular, Mycobacterium vaccae, has recently been found capable of uplifting your mood! Most gardeners claim that gardening is their therapy. Ends up, they were right!
Microorganisms, like other living things, can be poisoned with herbicides, pesticides, and fungicides. The best way to keep a healthy balance of microorganisms in your soil is to keep the soil healthy. Very often, chemicals cause too much change too quickly. Regularly adding compost to your soil is the best way to keep your soil healthy.
I hope this information inspires you to grow more of your own food. You can ask your garden questions on my Home page.