Like all life on earth, plants need water to survive and grow. Indeed, like humans, water is the primary element that makes up the structure of plants. Human bodies are comprised of around 70 percent water, but in plants this proportion can be as much as 95 percent. Water is also essential to the way a plant receives nutrients and provides energy for itself. Thus, water is arguably the most essential substance required by plants. That is why many elements of permaculture design – from using swales and contouring to slow runoff from the land and allowing it to sink into the soil to mulching to prevent evaporation of moisture from the soil surface – emphasis the preservation of water so that it can be provided to plants.
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