I woke to the sound of rain beating on the roof - or I imagined that sound. Later, I studied the sidewalk to see if I imagined it. I did.
Gardeners dream about rain, because there is no substitute for the life generated by this miraculous free substance. Nitrogen is abundant in the atmosphere but useless for plants as a gas. In fact, nitrogen is so neutral that Dow Chemical pulls it from the air, via a service company, and uses the gas to prevent explosions and fires.
However, when nitrogen is fixed, the building-block of life begins to do its work. The graphic above seems to diminish the effect of lightning making the rain into a liquid fertilizer. However, the small amount of useful nitrogen created by lightning translates into tons of fertilizer on the ground, as dry straw-colored grass will reveal after one soaking rain. The yellowed grass, which tends to overgrow and get over-thirsty from man-made fertilizer, will green up during one rainstorm.
Where does the rest of the useful nitrogen come from, apart from the chemical industry? One source is animal manure, which ranges in content from very hot (chicken, rabbit) to cool (horse, cow). Birds offer their tiny amounts, often with seed included. I routinely cut down enormous Pokeweed plants. They grow, flower, and fruit in any size imagined, but favor the jumbo size, seven feet tall with outstretching branches. Over sixty bird special love pokeberries, so the weeds are all free bird-feeders.
Green plant matter is also a source of useful nitrogren. Although straw is not green, and dried grass looks like straw, both retain their nitrogen and make compost hot when nitrogen-loving bacterial feed on the remains. That is why I wonder about people mowing their lawns, throwing away the clippings, and buying fertilizer to make the lawns green. Mulched clippings left on the lawn would do far more than man-made fertilizer additions.
Plants also fix nitrogen, but that is giving the plant too much credit. Bacteria take nitrogen from the air, converts it, and stores it in nodules on the roots. This donation improves the soil. Clover - often despised, feeds nitrogen to the grass, The more clover, the better.
A common weed here is Hogweed, which is a legume that adds nitrogen to the soil.
Gardening Knowhow - Nitrogen
How Do Plants Fix Nitrogen?
Nitrogen fixing plants do not pull nitrogen from the air on their own. They actually need help from a common bacteria called Rhizobium. The bacteria infects legume plants such as peas and beans and uses the plant to help it draw nitrogen from the air. The bacteria converts this nitrogen gas and then stores it in the roots of the plant. When the plant stores the nitrogen in the roots, it produces a lump on the root called a nitrogen nodule. This is harmless to the plant but very beneficial to your garden.
How Nitrogen Nodules Raise Nitrogen in Soil
When legumes and other nitrogen fixing plants and the bacteria work together to store the nitrogen, they are creating a green warehouse in your garden. While they are growing, they release very little nitrogen into the soil, but when they are done growing and they die, their decomposition release the stored nitrogen and increases the total nitrogen in soil. Their death makes nitrogen for plants available later on.
How to Use Nitrogen Fixing Plants in Your Garden
Nitrogen for plants is essential to your garden but can be difficult to add without chemical assistance, which is not desirable for some gardeners. This is when nitrogen fixing plants are useful. Try planting a winter cover crop of legumes, such as clover or winter peas. In the spring, you can simply till under the plants into your garden beds. As these plants decompose, they will raise total nitrogen in soil and will make available the nitrogen for plants that are unable to get nitrogen from the air. Your garden will grow greener and more lush thanks to plants that fix nitrogen and their beneficial symbiotic relationship with bacteria.
Read more at Gardening Know How: Nitrogen Nodules And Nitrogen Fixing Plants http://www.gardeningknowhow.com/garden-how-to/soil-fertilizers/nitrogen-nodules-and-nitrogen-fixing-plants.htm
Earthworms
Earthworms seem even more insignificant than birds, but they add up too. Their kidneys produce nitrogen from the bacteria breaking down organic matter in the long digestive tubes. The total earthworms in one acre can add up to a one ton animal, so the fertilizer produced from kidneys is not unremarkable. Besides, the earthworm castings (manure) concentrate nitrogen compounds, and concentrate other needed ingredients for good soil.
Nitrogen is essential to most plants and is the building block of protein.
The Creating Word gave us all these creatures and plants to work together, engineered them to recycle and save what is good, detoxify what is bad, and still manages them now to provide that Balance of Nature we heard about in science classes.
