[Plant Factory Questions] Explaining the Potential of Rice Hydroponic Cultivation

Hello everyone! I’m Shohei.

Have you ever heard of rice in a plant factory?
You don’t hear about factory-produced rice, do you? But rice can actually be cultivated in a plant factory.

Plant factories use advanced environmental control technology to produce vegetables and fruits year-round and in a planned manner.
By adopting hydroponics and optimizing factors such as light, temperature, humidity, and carbon dioxide concentration, it is possible to stably produce high-quality agricultural products.

However, when it comes to rice cultivation, it is technically possible, but there are still many challenges to commercialization.

This article will compare the characteristics of plant factories with the cultivation characteristics of rice and explain in detail the potential and challenges of rice cultivation in plant factories.

If you’re wondering, “Why do plant factories only grow leafy vegetables?” please refer to the following article.

Plant Factory Characteristics and Required Cultivation Item Conditions

In plant factories, it is important to recover investments as quickly as possible because high-priced equipment investments are required. Therefore, crops that grow quickly and have a high turnover rate tend to be selected.

Also, in order to introduce high-cost equipment, a certain level of sales price is required, so high-priced items are needed.

Especially when using artificial light, the running cost of the lighting is a significant burden. If the plant being cultivated has a large proportion of inedible parts, light energy is wasted. Therefore, items with a high proportion of the harvesting part are suitable.

Based on these conditions, lettuce, herbs, and strawberries are the main cultivation items in plant factories.

Rice Cultivation Characteristics and Compatibility with Plant Factories

Rice has a longer growth period and a relatively lower price compared to other plant factory-suitable items.

Lettuce can be harvested in about a month, while rice is harvested about twice a year, and it takes more effort. This is because lettuce is a small leafy vegetable that grows quickly, while rice grows large and takes time to harvest the mature rice.

Also, rice has low value in parts other than brown rice or polished rice, such as chaff, leaves, and stems, which are discarded. In plant factories, the high running cost means that discarding more parts wastes the input cost.

Furthermore, rice is consumed in large quantities as a staple food, so it is necessary to keep the price low, and selling it as a premium product is limited. Therefore, it is not easy to secure profitability that matches the high-cost equipment investment.

This is similar to what was written in the previous article about the relationship between “plant factories and grains.” Please refer to this article as well.

From the above points, it can be considered that the cultivation characteristics of rice do not necessarily match the characteristics of plant factories.

Current Challenges and Future Potential

In fact, research-level studies have shown potential for rice hydroponic cultivation.

But it hasn’t been commercialized yet.

This is because the cultivation characteristics of rice and the high-cost structure of plant factories make it difficult to achieve profitability as a business.

Also, if the growth period is long, it takes time to recover the initial investment in plant factories.

However, if the future brings demand for high-priced rice for medicinal use or a time when safety and stable production are prioritized, rice cultivation in plant factories may become more widespread. Rice for medicinal use that contains high concentrations of specific ingredients could allow for higher sales prices, making cultivation in plant factories possible.

Also, if consumer awareness of food safety and stable supply increases, there may be demand for plant factory-produced rice, even if it is high-cost.

Summary

This article explained the current challenges and future potential of rice cultivation in plant factories.

In conclusion, it can be said that rice cultivation in plant factories is technically possible, but currently lacks practicality as a business.

Rice has a long growth period and a low price, making it difficult to secure profitability in a high-cost plant factory structure.

What are the advantages of hydroponic cultivation of rice?

The advantages of hydroponic cultivation of rice are that it is not limited by soil, and nutrients and water can be precisely controlled. This is expected to lead to stabilization of quality and improvement of yield. There are also advantages in avoiding continuous cropping damage and suppressing the occurrence of pests and diseases.

What is the difference between hydroponics and plant factories?

Hydroponics is a general term for methods of growing plants with nutrient solution instead of soil, and plant factories also use hydroponic systems. Plant factories are characterized by using environmental control technology, in addition to hydroponics, to control light, temperature, humidity, and carbon dioxide concentration to a high degree, enabling year-round and planned production.

What is the difference between plant factories and open-field cultivation?

Open-field cultivation is a traditional form of agriculture conducted in outdoor natural environments. On the other hand, plant factories are a form of agriculture that creates artificial environments indoors and conducts advanced environmental control. Open-field cultivation is susceptible to weather influences, while plant factories have the advantage of enabling year-round and planned production. Also, plant factories have the advantage of preventing the entry of pests and diseases, and minimizing pesticide use.