There are many reasons why gardeners choose to grow their crops using soil-less hydroponic methods instead of traditional soil-based methods. Some of hydroponics key advantages include more space-saving, more energy/water efficient, less weeding, and fewer pests to contend with. Hydroponics also allows the grower more control and creativity with their crops so that they may provide the most ideal conditions for plants. However, the single most compelling reason for gardeners to switch to soil-less gardening is its ability to significantly increase crop yield. Let’s review the factors that influence hydroponics yield in order to demonstrate why this type of gardening is better than soil in nearly every respect.
Misconceptions about Hydroponics Yield
Some people are under the impression that hydroponics will produce much larger plants than soil. This isn’t necessarily the case. Each seed has its own genetic code which determines the plant’s size, flavor, and yield potential. In other words, you can’t transform a cherry tomato into a Roma tomato, but you can turn a cherry tomato seed into the genetically best possible cherry tomato plant if you provide the perfect growing conditions. Hydroponics gardening gives plants the best opportunity to reach their full genetic potential. More often than not, this translates into healthier, larger, and more flavorful crops.
It can be difficult for plants to reach their highest genetic potential in common soil. This is because there are hundreds of variables in soil’s makeup that can influence a plant’s growth. Hydroponics, on the other hand, gives the grower the ability to micromanage and control the growing conditions so there are no surprises from Mother Nature. Soil-based plants use a lot of energy to seek out their food source, while hydroponics plants are given exactly what they need when they need it. Thus, hydroponically-grown plants can direct all their energy into producing higher yields, denser vegetation, faster growth, and more flavorful crops. It is more likely that hydroponic crops reach their genetic potential, and thus, is often considered a superior form of agriculture.
Hydroponics Yield Factors
So why exactly are the crop yields so much greater for hydroponics? Let’s look at the most important factors of hydroponics yield.
1. Year-Round Gardening Means More Crops Per Year
One of the most important factors influencing hydroponics yield is its ability to grow crops indoors and year-round. Field crops are often limited to one harvest per year because of frost and other weather variations. Since greenhouse and hydroponic crops are grown indoors – away from Nature’s elements – you can cultivate 12 one-month crops, 5 seventy-day crops, or whatever crop harvesting time frame you choose. As a result, you can increase crop yield each year by a factor of 2x to 8x by growing indoors and year-round with hydroponics.
2. Higher Plant Density Allows for More Crops Per Acre
Hydroponics allows for higher plant density in one or more of the following ways: hydroponic crops can be grown 1. closer together than in soil, 2. grown vertically as opposed to horizontally, 3. in layers, and 4. with much less walking space between rows. Employing any one of these methods can increase crop yields, but incorporating several can result in even more plant density. Overall, you can increase plant density by a factor of 4x to 16x with hydroponics.
3. The Crops you Choose May Increase Yield
Which variety of crops you decide to grow can influence the hydroponics yield. While you can cultivate nearly any crop in a hydroponics system, some will give you better results and a higher yield. For example, leafy crops – like lettuce, chard, kale, and arugula – produce great results, as do herbs like basil, chives, parsley, and sage. Tomatoes, peppers, and cucumbers can also result in high yields with hydroponics. Certain crops present more of a challenge – like watermelons and strawberries – but with special attention, they can also produce great results. On the other hand, root vegetables, corn, and plants that vine are not recommended for hydroponic gardening. Depending on the crop variety you choose, hydroponics can increase yields by 2x – 4x over soil farming.
4. Proper Lighting is Key
Plant growth is dependent on adequate lighting. They tend to do best with a light of wavelengths in the 360 – 760 nm (nanometers) range. Plant photosynthesis responds to blue light (around 430 nm) and red light (around 660 nm). Plant germination, stem, and flower growth thrive when red light is around 660 nm and infrared light wavelength is around 735 nm. White fluorescent lights provide a light spectrum which includes these preferred wavelengths. While field grown crops depend entirely on the sunlight for their growth, greenhouse or indoor hydroponic crops utilize grow lights to mimic the sun’s natural light. With the proper grow lights, hydroponics plants will receive the optimal spectrum of light throughout the year regardless of what the sun is doing outside. Good lighting can increase hydroponics yield by 1x – 2x.
5. Water Plays an Important Role in Crop Yield
Water is clearly one of the most important factors influencing crop yield. After all, the water-weight of fruits and vegetables is 86% and 90%, respectively. Field-grown crops are susceptible to droughts and inconsistent rain patterns – too much or too little water can wreak havoc on crops. Water can be managed much more efficiently with hydroponic and greenhouse crops. The proper water management can translate to a 1x – 2x increase in yield.
6. The Efficiency of Hydroponic Fertilizer
In hydroponics, a fertilizer is mixed with water to create the nutrient solution. This nutrient solution is typically pumped into the grow bed to feed the plant’s roots. Hydroponics allows plants to get the correct nutrients they need when they need it. Soil grown crops don’t have it as easy. If they don’t get the proper nutrients at the right time, crops will suffer. Hydroponics provides a much more efficient way of delivering nutrients to plants. Yield can be multiplied by a factor of 1x – 2x if greenhouse or hydroponic crops are feed properly.
7. Managing Temperature and CO2 can Increase Yield
Temperature and CO2 are important factors in plant growth. Each crop variety has its own preferred temperature, and this varies depending on its phase of growth. However, most plants respond best when temperatures are kept in the 75F to 85F range. With hydroponics, the yield can be multiplied by 1x – 2x if temperatures are kept within ideal levels.
As for carbon dioxide, the more CO2 in the air, the faster a plant grows. It is proposed that two to five times the normal amount of carbon dioxide may be the optimal amount. Tomato and cucumber growth rates can be increased by up to 20% – 40%, while the faster growth rates in lettuce can allow for an extra crop grown each year. Carbon dioxide enrichment can increase yield in hydroponically-grown crops by 1x-2x.
8. Other Factors that Influence Hydroponics Yield
There are several other factors which affect plant growth. These include relative humidity in the growing environment, the amount of oxygen the plant’s roots are exposed to, and the proper pollination. Hydroponics allows you to control all of these things to the ideal levels, but it requires close attention to get it right. Another clear advantage to growing crops indoors and without soil is the protection from storms and bad weather, as well as the near elimination of pests. While insects, mammals, birds, pathogens, and weeds can destroy around 33% of field crops, indoor hydroponic and greenhouse crops experience very few of these problems.
One issue hydroponics gardeners must prevent is waterborne disease, as this can devastate an entire crop. Grow media should be sterilized after each grow so as to prevent diseases from one grow to the next. Certain organic soil fertilizers – like manure and waste – can also introduce disease, whereas a hydroponic nutrient solution mix of water and fertilizer eliminates this risk. In total, all of these “other factors” can increase hydroponics yield by 1x -2x.