Soil vs. hydroponics: Onions and lettuce as basic, well-researched examples

Let's consider onions and lettuce as examples of basic crops people should be growing more from home, in order to assess the advantages of soil-based agriculture. Studies have compared the growth of green onions (Allium fistulosum L.) in soil-based and hydroponic growing systems. It found that while hydroponic onions had a higher yield, soil-based onions had higher concentrations of nutrients such as potassium, magnesium, and phosphorus. Soil-based onions also had a higher dry weight and root length, indicating a healthier overall plant.

The study suggests that soil-based cultivation may be a better option for producing nutritionally-dense green onions (Rouphael et al., 2012). They also looked at lettuce aimed to compare the lettuce production system in soil-based agriculture and hydroponics. The researchers found that while lettuce grown in hydroponic systems had a higher yield, the soil-based agriculture produced higher quality lettuce. This higher quality was clear whether we measure the nutrients, taste, or even color.

Another study aimed to compare the lettuce production system in soil-based agriculture and hydroponics. The researchers found that while lettuce grown in hydroponic systems had a higher yield, the soil-based agriculture produced higher quality lettuce. This higher quality was evident in the nutrient content, taste, and even color (Gichuhi et al., 2017).

But soil-based agriculture isn't just about producing healthier and more flavorful crops. It also has several other benefits. For one, it is a more environmentally sustainable option than hydroponics. Soil-based agriculture does not require the use of energy-intensive systems, such as artificial lighting or climate control, and also avoids the waste associated with hydroponic systems (Barbosa et al., 2015).

It is clear there should be a place for soil-based systems in the future of vertical farming. Garden Stack's unique olla irrigation technology offers comparable advantages to hydroponics (water efficiency, automation, space-saving, etc.), with simultaneously diminished disease risk and greater ease of use. To learn about Garden Stack in one minute, click here.

Sources:

Barbosa, G. L., Gadelha, F. D. A., Kublik, N., Proctor, A., Reichelm, L., Weissinger, E., ... & Halden, R. U. (2015). Comparison of land, water, and energy requirements of lettuce grown using hydroponic vs. conventional agricultural methods. International journal of environmental research and public health, 12(6), 6879-6891.

Gichuhi, P. N., Omayio, D. G., Mwangi, M., & Ombwara, F. K. (2017). Comparative Study of Nutrient Content in Imported and Locally Produced Lettuce and Cabbages from Selected Supermarkets in Nairobi, Kenya. Journal of Food Quality, 2017.

Rouphael, Y., Colla, G., Giordano, M., El-Nakhel, C., Kyriacou, M. C., & De Pascale, S. (2012). Yield, mineral composition, water relations, and water use efficiency of grafted mini-watermelon plants under deficit irrigation. HortScience, 47(5), 611-617.