Water Retention Landscape Techniques for Farm and Garden
As the effects of climate change pursue, the necessity to build resilient communities and farms becomes ever more apparent. Often farmers are stuck dealing with incessant rainfall, hurricanes, floods and droughts. Many innovative water conservation methods have emerged and are being practiced all over the globe — some have been practiced for centuries and others are much newer, however each require different types of resources. Most of these methods provide additional benefits as well, including soil conservation and improvement, enhanced biodiversity, and increased yields. There really is no limit to how many of these methods can be practiced alongside each other and the techniques most efficient for your particular farm will depend on many factors, including geography, climate, size and type of farm. Below is a list of 12 water conservation techniques being used around the world.
1. Mulch: Using natural materials such as straw, leaves, twigs, small branches and paper products as mulch helps hold in moisture and therefore conserves water. As the mulch decomposes it becomes an excellent source of food for the bacteria and organisms living in the soil, enhancing the soil quality. Mulch deters weed growth, and when used over time, revitalizes soil and promotes better plant growth. In The One-Straw Revolution Masanobu Fukuoka explores this idea in great detail.
2. Deep Root Plants and Trees: Plants and trees with deep roots have the ability to store water and not only survive periods of drought, but also provide water to plants that are grown around them. A great example of this is the enset plant, a calorie-dense fibrous plant native to Ethiopia. Furthermore, trees also store carbon dioxide (CO2) and therefore combat climate change. A recent study found that trees with deep roots were found to store up to five times the CO2 typically believed.
3. Stones: Permaculture pioneer and international agricultural consultant, Sepp Holzer, utilizes stones to retain water and create microclimates. This allows trees and plants to grow in climates in which they are not naturally found. He places large stones around trees, for example, to trap heat and reflect it back towards the plant. When stacking rocks he is able to produce a cooling effect which then traps moisture and creates condensation, acting as a natural drip irrigation system. Holzer explains that “only when the soil is cooler, when the vegetation is giving shadow, then it attracts the water and lets it seep in.”
4. Terraces: These are layers or steps built into a hill, mountain or sloped plane. This prevents water from just running down the hill, often dragging soil with it and provides a more effective design for farming on inclined surfaces.
5. Swales: Swales are ditches with flat bottoms that collect water. They are usually dug out on the outer contours of a particular landscape for the purpose of holding and sinking the water. This helps hydrate the soil. Swales prevent water from just running down the hill, often dragging soil with it, and provides a more effective design for farming on inclined surfaces.
6. Berms: A raised plot of land or barrier used to prevent runoff. When designed next to a swale the two can be the most efficient and beneficial, as the berm can direct water to the swale and pull water from it for the plants growing on the berm as needed, conserving water and preserving the soil.
7. Hugelkultur: Translates loosely in German to ‘mound culture’. Hugelkultur is designed by digging out a large hole, laying down logs and other wooded and natural debris and then covering it with soil which plants and trees can then be harvested on. As the logs decompose they provide nutrients to the organisms living in the soil, as well as act as a sponge, soaking up water during rainfall and releasing it into the soil as needed; therefore Hugelkultur does not need watering, even in dry climates and during droughts. See also here.
8. Ollas: Are unglazed, porous clay pots that are planted underground near plants and deter water evaporation or run off. Water is poured directly into the olla and it releases the water to the root system of the plant as needed.
9. Drip Irrigation: Is a watering system that allows water to drip slowly out onto the soil, therefore minimizing water runoff, soil erosion and evaporation of surface water. These systems can be as complex as having many hoses, filters and pressure regulators, or as simple as having homemade bucket systems, using gravity to drop the water onto the crops.
10. Rainwater Harvesting: Is a method of retaining water whereby large barrels or tanks are used to collect rainwater as it falls and runs off rooftops. This water can then be used to water one’s garden or filtered and used for indoor use.
11. Greywater System: Greywater is previously used water from sinks, bathtubs, and washers, for example, which can be collected for reuse. This is a water retention method that prevents water from being used only once, permitting it to be filtered and recycled in home, for reuse.
12. Chinampas: Often referred to as “floating gardens” is an ancient Mesoamerican agriculture method where artificial islands or peninsulas are created by piling up mud, lake sediment and other decaying vegetation until it protrudes above the water. Seeds are then planted on these plots, using the lake water for irrigation, therefore, never needing to be watered. This method is known to produce extremely high yields and provides an ideal environment for plants and fish, acting as a natural aquaponic system.
These methods are just a few examples of how we can design our systems to conserve and reuse water. There are many other methods that you can integrate into your permaculturally designed system. Feel free to share any that were left out, or how you have designed your system using the above methods, in the comments below.