WATER vs SOIL FARMING: WHICH METHOD IS BETTER?
Humanity has been farming in the soil since the beginning of time. And it has been our primary source of nutrition. However, soilless methods, like hydroponics, are growing in popularity.
Following is a comparison of hydroponics and soil methods. Is one better than the other?
Soil is a mix of sand, clay, silt, water, decomposing organic matter, air, minerals from rocks. It’s the percentage of these that defines whether it is good soil for planting or not. The best soil type has a good mix of these ingredients, and its called loam, topsoil or sometimes referred to as black gold. It should also have a pH level of around 6.
The processes that generate high-quality, fertile topsoil can take centuries. But due to the growth in population, the world is ploughing through that resource at an alarming rate. About 40% of the world’s land has already been taken over by agriculture, while livestock grazing and expanding urban areas are taking further chunks out of what is leftover.
Furthermore, erosion, compaction, nutrient imbalance, pollution, acidification, waterlogging, loss of soil biodiversity and increasing salinity have been affecting soil across the globe, reducing its ability to support plant life and grow crops.
- Soil is abundant everywhere – Soil is the natural growing medium for most plant species since most plants grown in soil.
- Soil farming is well developed – There are machines and products to help with nearly every aspect of soil farming.
- Cheaper startup cost – Soil-based farming is more affordable to set up initially, because, unless you have a big farm, you don’t need fancy equipment to grow your crops.
- It’s easy to do – All you need is to place the seed in the soil and water. Everyone can do it.
- Slower plant growth – In a soil-based system, the roots have to do more work for fewer nutrients and therefore produces slower growing crops.
- Brings more pests and diseases – Because of the different microbes that are usually present in the soil, soil farming suffers from more pests and diseases than other methods. This method also requires the use of pesticides and herbicides to grow healthier crops.
- Requires more water – Soil farming depends on available water to produce high yielding crops. There is a high rate of water loss, in the soil and evaporation.
Hydroponic farming is the method of growing plants without soil. The nutrients needed by the plants are readily available, transported in water.
The plant’s roots are usually supported by a non-soil growing medium, like coconut coir, perlite, clay pebbles, Rockwool, etc., which allows the movement of the roots while being immersed in a nutrient solution.
- Faster plant growth – Hydroponic farming speeds us the growth rate of crops due to the easy access to nutrients in the water-based solution. Therefore, you can replant many more times in the year.
- No weeding – Weeds only grow in soil; hence there are no weeds in a hydroponic system.
- Fewer pests and diseases – Microbes, pests, and diseases come mostly from the soil. Because a hydroponic system uses no soil, the presence of these pests and disease-causing organisms are greatly reduced. This also means that there is no need to use pesticides and herbicides, making a better quality crop.
- More water-efficient – Hydroponic systems use only 10% of the water used in soil farming.
- More space efficient – You can have a vertical hydroponic system in a 42 sq.f area, that will grow over 4600 heads of lettuce in a year.
- Can be grown anywhere – Because of the use of lights used in most hydroponic systems, you don’t need to be outdoors or in a greenhouse. This makes this method ideal for urban areas, where you can set up a system just about anywhere.
- Higher capital cost – The major barrier to hydroponic farming is the cost of setting up the equipment.
- Need specialized training – You’ll need to learn how to use the system before you start planting.
- It’s more work – Unlike soil farming, where you plant the seed and leave it until harvest time, hydroponic farming requires daily attention—more work but also more yield.
- Higher energy costs – Hydroponic systems rely heavily on lights for plant growth. You can use LED lights, which require less energy to use, but they are more costly than regular fluorescent lights. However, fluorescent lights use a lot more energy and produce heat. LED lights produce no heat.
There are various types of hydroponic systems like aeroponics and aquaponics. Although these are variations of a hydroponic system, there are significant differences between the three.
If you are considering getting a hydroponic system, which system is better suited for your production? Let us look at the differences.
In hydroponics, you replace the soil with another medium for the plants to grow in. The growing medium works like a foam by soaking up water and move it. The plants get the nutrients that they need from the water, which is usually a nutrient-rich solution consisting of various ingredients and therefore making it possible to control the number of nutrients the plants get and when. The nutrient solution and its formulation will depend on the kind of plants that you want to grow.
By applying nutrients directly to the roots, plants can be grown in a smaller space and they will grow as much as two times as fast as soil-grown plants. A smaller space allows for the plants to be concentrated, allowing for more production. When the root system is contained in a closed channel, there is less evaporation and water consumption.
This method is the more affordable of the hydroponic systems.
Aeroponics is a type of hydroponics. Still, instead of a growing medium, it uses a support platform with a flexible collar to support the plants while the roots hang below in an enclosed chamber.
In this system, the roots of the plants are misted with nutrients, water, oxygen. Using a closed-loop system, 95% less water than field farming is used, and 40% less than hydroponics.
The design of this cultivation system reduces the plant’s need for water and nutrients. And the plants will use a significantly lower percentage of both then when using the hydroponics system.
Since the plants in aeroponics are not competing for nutrients, each requires less space, and this provides for more efficient space utilization as you can have many plants in one small area.
With aeroponics, a grower can take the exact same seed from the field and grow it in half the time as a traditional field farmer, leading to 390 times more productivity per square foot than a commercial field farm. Using aeroponic technology, researchers discovered the yields of plants grown were more than 30% larger on average.
With traditional growing methods in soil, a lot of space is required. But growing aeroponics vertically requires only 10% of the room traditional farming needs.
This is a more sensitive system and requires a lot of attention and skill.
It also requires a significantly higher initial investment.
Aquaponics uses a combination of aquaculture (raising fish) and hydroponics. Aquaponics systems work by using the waste from fish to naturally provide nutrients to nearby water-grown plants.
One benefit is that producers grow plants and fish in a closed system, where the water cycles through the system with very little lost. By adding fish into the equation, a natural ecosystem exists, in which fish, plants, and bacteria flourish off each other. The waste from fish and the living bacteria in an aquaponics system delivers all of the nutrients the plants need. The fish and the bacteria create a cleaner, non-toxic environment for the fish to live in.
About two gallons of water is needed for every pound of fish. The fish will be living in a tank environment. Therefore, for maximum growth, the fish need to be able to live in crowded conditions. Fish that grow fast are ideal, as the growth of the plants is reliant on the waste excretion from the fish.
One of the significant advantages of aquaponics, besides growing and harvesting fish for protein, is that it is a natural and organic process. Aquaponics is proven to achieve healthier growth, suppressed disease rates, and less maintenance.
Because hydroponics, aeroponics and aquaponics do not use soil, they can be established indoors in locations that have cold, severe climates. These growing methods can also be used in localities that have poor, sandy soil. Water farming could be the way that we feed our growing population.
At Cultivating Hope Foundation we want to produce vegetables using a variety of water methods so we can then donate the produce to the local families in need and the food bank . Once our systems are set up we will be accepting visitors to see how everything works.
If you would like to make a donation to help us purchase one of these systems please visit www.cultivatinghope.ca/donate.