Modern agriculture has two significant problems that need to be urgently addressed: global water scarcity and declining soil fertility. Looming over these issues is the critical question: How will we feed approximately 10 billion people by 2050?
Smart soil, which uses less water and fertilizers, allows farmers to grow crops even in scarce water conditions and release nutrient dosages as needed. As a result, farming practices can become more sustainable. However, achieving this transformation requires strategic investment across the entire food sector value chain.
This article examines the potential of smart soil to address water scarcity and soil fertility problems, helping to boost sustainable food production for the increasing population while creating new investment opportunities.
What is smart soil?
Smart soil is a newly engineered soil type that uses a hydrogel material to capture water from the atmosphere to keep plants hydrated. It also provides a constant supply of nutrients to the plants through the controlled release of fertilizers. Initially discovered at The University of Texas at Austin, smart soil may be a viable option to grow plants without the need for frequent irrigation or fertilization.
How does smart soil work?
Smart soil is made of hydrogels that act as reservoirs that absorb and retain moisture. Hygroscopic agents embedded in the hydrogels increase the soil’s capabilities for absorbing moisture. The agents ensure that water is available even in dry conditions.
Water is released due to the stimuli received by the thermoresponsive polymers. The polymers retain water at cooler temperatures, and at higher temperatures, they release it. 
Figure 1. The process of how smart soil works
The interpenetrating polymer networks from secondary polymer networks aim to improve water retention capacity. These networks increase the swelling ability of the hydrogel, allowing it to hold more water and release it over time.
All of the processes are controlled by the release mechanisms. These are in charge of fine-tuning the delivery of both water and nutrients, responding to environmental conditions such as temperature and humidity.
Key problems of existing agriculture:
Agriculture consumes 70% of the Earth’s freshwater supply. As the global demand for food rises, the pressure on freshwater supply is also likely to increase. In the western United States, irrigated agriculture is the largest consumer of freshwater, where 30% of sub-basins experience high-to-severe irrigation scarcity.
In addition to water scarcity, declining soil fertility has led to excessive reliance on fertilizers. In North America, more than 40% of corn and soybean fields often receive nitrogen and phosphorus above recommended levels.
These challenges are further compounded by climate change, which disrupts the four key pillars of food security:
- Availability
- Access
- Utilization
- Stability
Despite these difficulties, there remains an opportunity to implement changes that can steer agriculture toward a more sustainable future.
Can we make agriculture practices sustainable and still meet the increasing food demands of growing populations? Find out now in our Intelligence Brief.
Is smart soil a promising solution?
Smart soil is emerging as a viable solution for modern agricultural challenges. Here, we explore how smart soil paves the way for more sustainable agriculture.
Addresses water scarcity in agriculture:
Smart soil offers a more efficient solution to managing freshwater resources in agriculture than regular soil. Engineered hydrogels within the soil respond to changes in humidity and temperature, capturing and releasing water based on environmental conditions.
For instance, at 90% relative humidity, a hydrogel can absorb up to 1.88 grams of water per gram of hydrogel and release 95% of it within 4 hours during the day when the temperature hits 40°C.
Figure 2. Smart soil saves more water than traditional soil
Through this mechanism, smart soil achieves about 40% water savings compared to traditional agricultural methods. This water resource management is crucial in regions facing water scarcity.
Improves soil fertility and reduces fertilizer use:
The hydrogel-infused soil releases nutrients based on plants’ needs and environmental conditions. At 90% relative humidity and 6 mL irrigation every three days, the hydrogel releases nutrients sustainably, with only 59.45% of the fertilizer released over 16 days.
This controlled release reduces the risk of nutrient leaching into waterways, a common problem with traditional fertilization methods. The slow-release mechanism reduces the need for frequent fertilizers and contributes to more resilient agricultural practices.
Boosts crop yields and ensures plant survival:
Self-irrigation and slow-release fertilizer hydrogels (SISRH)-based soils have shown increased crop yields. They provide 66.07 grams per liter of water compared to 35.32 grams per liter in sandy soils. This substantial difference highlights the efficiency of smart soil in optimizing water and nutrient delivery to plants.
Furthermore, plants grown in SISRH soil show a 100% survival rate under adequate irrigation. These plants also grow stems that are 138% to 171% longer than those in sandy soil, even in varying humidity conditions. Such improvements in plant growth and yield make smart soil a promising solution for meeting the increasing global demand for food.
Reduces the need for labor and other resources:
The controlled release of water and fertilizer reduces the need for frequent irrigation and fertilization. This helps to lower labor demands and also cuts down on the resources required for farming operations.
The self-regulating properties of smart soil mean that farmers can maintain healthier crops with fewer resources. This reduction in resource consumption helps to reduce operational costs and contributes to more sustainable agricultural practices.
Is smart soil gold for business?
The relevance of hydrogel-based smart soil goes beyond its theoretical and academic appeal. It can potentially offer tangible benefits for the agriculture sector.
The concept of smart soil aligns with the growing demand for regenerative agriculture. As climate change intensifies, the farm sector is increasingly pressured to adopt practices that conserve water, reduce emissions, and improve soil health.
The financial implications for improving agricultural practices are substantial, with an estimated $700 billion needed in capital expenditure over the next 30 years. However, the implementation of climate-friendly agricultural practices, such as smart soil, could mitigate nearly 170 GtCO2 equivalent and, at the same time, can generate nearly $10 trillion net financial return by 2050.
As a result, companies that invest in eco-friendly agricultural practices will likely gain direct financial returns and larger market share due to the increasing adoption of green initiatives.
The future of smart soil:
The ongoing academic research is helping to develop new materials and technologies to improve smart soil’s performance. For example, nanotechnology advancements are improving smart soil’s efficiency in saving water and delivering nutrients.
Additionally, alternative approaches include integrating smart soil sensors and digital technologies to allow for the real-time monitoring of soil conditions. This will allow for more precise management of agricultural resources.
While the promise of smart soil is significant, its widespread adoption still faces several obstacles. As with all new technology, the main problem is related to the high costs of the materials and the need for specialized knowledge.
However, as research continues and investments increase, smart soil is expected to become more accessible and affordable. Ongoing research and targeted investments will be essential in fine-tuning smart soil technologies, allowing them to drive a more resilient and sustainable future for agriculture.
