Nutrients in the Garden - The Nitrogen Cycle

g'day welcome to i cultivate my name's Steve understanding the way nutrient cycle in the vegetable garden is critical to productive gardening so today we're going to be looking at that critical nutrient nitrogen the main reason why nitrogen is critical to the growth in the health of all organisms including the plants in your garden is because nitrogen is essential to the production of enzymes now all enzymes are proteins and proteins contain nitrogen so basically what it comes down to is if you don't have nitrogen you don't have enzymes and therefore you don't have healthy plants the problem is that even though seventy-eight percent of the atmosphere is nitrogen plants are unable to take that nitrogen directly from the atmosphere into themselves and produce these enzymes plants have to access their nitrogen in the form of nitrates directly from the soil so there's the link the link between nitrogen and the health of your plants your plants access nitrogen in the form of nitrates from the soil and then they use the nitrogen to produce proteins and many of those proteins are in fact enzymes necessary for the health of plants as a gardener it is much more important to understand how nitrates get into the soil if you understand that you can manage their levels and ensure that your plants always have enough nitrate for healthy growth and development so here's the trick seventy-eight percent of the entire atmosphere consists of nitrogen but that nitrogen cannot be used by plants so somehow or other that nitrogen is going to get down into the soil in a form that plants can use the first step in that process is to convert the atmospheric nitrogen into substances such as ammonia and nitrites now that process is performed by a whole range of different types of bacteria now collectively those bacteria are performing a function that is known as nitrogen fixation but these substances are still not in a form that can be readily used by plants so the next step is for these substances here our ammonia and nitrites to be converted into another compound called nitrates that process is known as nitrification and performed by yet another set of bacteria now these nitrates can be taken up by plants so as complex as it seems the way in which nitrogen from the atmosphere is made available to plants as nitrates is by the critical action of these bacteria no bacteria means no nitrogen in the form of nitrates available to our plants so these nitrates can now be absorbed by our plants and of course our plants will be eaten by various animals and in doing so are absorbing the nitrogen in the form of protein and so on as well so remember our plants cannot take nitrogen directly from the atmosphere that nitrogen is available to the plants as nitrates that have been taken from the atmosphere and converted by bacteria into these nitrates but of course the cycle can't finish there the nitrogen that is locked up in these compounds is somehow rather got to get back to the atmosphere and that's performed by another set of bacteria known as denitrifying bacteria now this is not the full story from a gardening perspective because there is a group of plants that is able to access its nitrates not from the soil but in fact from little nodules on its roots that contain these bacteria what this means is is that they're able to grow in soils that are deficient in nitrates soils that have low levels of nitrates because they're getting a lot of their nitrates not directly from the soil or from the bacteria contained in the nodules on their roots but we'll leave that for another video in another time I hope you found this video useful can I please ask you to subscribe to this channel and go to our website i cultivate dotnet and become a member of the community thanks for watching