Is food grown hydroponically as healthy as soil-grown crops?
Hydroponically grown lettuce has claimed a spot next to the organic variety in the grocery store, causing consumers to wonder which is healthier. When comparing hydroponic produce to regular soil-grown crops, it depends. Numerous scientific studies have reached varying conclusions, some showing hydroponic tomatoes have more vitamin C and others concluding they are lower in antioxidants.
By Emily Folk
Are hydroponics healthy? While the jury is still out, there are a few factors that can help consumers decide which growing type they prefer. Whether hydroponics or regular crops are healthier remains inconclusive, but there are ways to determine which growing method contributes to the overall health of the plant. By identifying the factors outlined below, we can compare the health benefits of hydroponics to those of conventional produce.
Is It Organic?
Sustainable farming focuses on soil fertility, working to improve carbon levels and produce healthier plants. In terms of nutrient value, organic produce may not necessarily be better than conventionally grown food. However, there are other factors to consider. Scientists agree that organic produce may be healthier when considering pesticide residue, which can be particularly damaging to human health.
While some growers disagree with labeling hydroponics organic, it is important to note that many hydroponic operations can be grown without pesticides. Many consumers are motivated to eat organic because it is more environmentally friendly than conventional agriculture, especially in the face of climate change.
However, hydroponics may also be a climate-smart solution for feeding the planet. Overall, like soil-grown produce, differentiating between conventional growing methods and more sustainable approaches is vital to the health value of the product.
Is It Bioavailable?
Nutrient bioavailability refers to what percentage of micronutrients, like phytochemicals and vitamins, are absorbed and utilized. Some vitamins and minerals are more easily absorbed in fresh produce, while others pass through the human body unused.
Nutrient bioavailability changes in the soil, making it difficult to compare the same plant grown in different conditions. With hydroponics, nutrients are delivered directly to the plant’s roots, removing any question of the quality delivered. However, the case can also be made that heterogeneous soil conditions make plant nutrients so potent, since they strengthen plants to fight against diseases.
Is It Oxygenated?
When comparing soil-less and soil-grown plants’ health, consumers should look into how each crop is oxygenated. Hydroponic systems require access to oxygen, considering the plant roots are submerged in water. While hydroponic growing systems enable farmers to deliver nutrients directly to plant roots, they also require close attention to the water’s acidity and temperature.
The plant’s overall health depends on whether it is oxygenated, a process that normally takes place naturally in the soil. Both soil-grown and hydroponic crops require oxygen to grow, and the lack of it is one of the most common factors in limited hydroponic plant growth.
Is It Fertilized?
Hydroponic systems deliver nutrient solutions, or fertilizer, directly to the plant through the water. The kind of fertilizer used in the hydroponic system has a direct effect on crop health. All nutrient solutions have a mix of macro and micronutrients. Examples of macronutrients include phosphorus, sulfur, nitrogen and potassium. Micronutrients include boron, copper, zinc, iron and manganese.
Soil-grown crops get their nutrients from the earth. The pressures of annual production often require farmers to use fertilizers seasonally, to restore any nutrient depletion the soil experienced during the prior growing season. Organic growers can utilize natural fertilizers, and many farmers use manure or fish meal to improve soil quality.
There is an obvious connection between soil health and a healthy plant, but with hydroponics, the path is not quite as linear. Does delivering the nutrients straight to the plant’s roots result in a better product?
The answer, unfortunately, is inconclusive. One study found that hydroponic lettuce had lower levels of carotenoids, including beta carotene, which is converted into vitamin A when consumed. Another found that hydroponically grown strawberries and raspberries had lower levels of fructose and glucose, as well as higher levels of ascorbic acid and polyphenolic compounds.
While it may seem like direct nutrient delivery would be more effective, the natural reactions between light, carbon and water seem to play a unique role in plant health compared to soil-less produce.
Are Hydroponics Healthy?
While scientists are still unsure of the benefits of hydroponics, it is worth comparing the factors that may make it a healthy option. The heartiest crops rely on quality soil, and unfortunately, many conventionally grown produce is grown in depleted land. They may need synthetic chemicals and fertilizers to grow at all.
A more sustainable option, organic cultivation, also relies on fertilizers to a certain extent. There is certainly a link between soil health and human health, but hydroponics may be a healthy alternative. When comparing the possible health benefits of hydroponics versus regular crops, it is essential to consider many factors.
Are hydroponics healthy? We aren’t sure yet. However, the research shows they are definitely a viable alternative to regular crops.
(Originally appeared at Conservation Folks.)