Oxygen Nanobubbles in Irrigation: The Science Behind Water Quality, Root Health and Crop Performance

Introduction

Water quality is fundamental to agricultural productivity. However, irrigation performance depends on more than the volume of water delivered to a crop. Dissolved oxygen, nutrient availability, soil structure, salinity, microbial activity and the condition of irrigation infrastructure can all influence the growing environment.

Nanobubble technology offers a way to modify the physical and chemical characteristics of irrigation water by introducing extremely small gas bubbles into the water. When oxygen is used as the gas, the technology can increase dissolved oxygen concentrations and influence conditions within the soil or growing substrate.

Research into nanobubble-enriched irrigation water has investigated its potential effects on plant growth, root development, nutrient release, soil properties and water-use efficiency. These effects are promising, but their magnitude depends on the gas used, its concentration, the crop, the growing medium and the wider irrigation system.

At Blue Planet South Africa, we consider technologies such as nanobubble generation within a broader, evidence-led approach to water management and environmental performance. The objective is not simply to introduce a technology, but to understand where it can address a defined problem and how its performance should be measured.

1. What are nanobubbles?

Nanobubbles are gas-filled bubbles with dimensions on the nanoscale. Unlike conventional aeration bubbles, which tend to rise through water and escape at the surface, nanobubbles can remain dispersed in water for extended periods under suitable conditions.

Their small size produces a high interfacial area relative to the volume of gas present. This characteristic, together with their interfacial properties and behaviour in water, has attracted interest in applications involving gas transfer, water treatment and biological processes.

In agricultural applications, the gas used to generate the bubbles is important. Oxygen nanobubbles are investigated primarily for their ability to increase and maintain dissolved oxygen and alter the oxygen conditions experienced by plant roots and microorganisms.

Nanobubble water is not a single, uniform treatment. Bubble characteristics, gas concentration, water chemistry, temperature and system design can all influence the outcome.

2. Dissolved oxygen and the root zone

Plant roots require oxygen for cellular respiration, the process through which they generate energy to support growth, nutrient uptake and other metabolic functions.

When soil or growing media become waterlogged or poorly aerated, oxygen availability can decline. This can restrict root function and alter microbial activity around the roots.

Oxygen-enriched irrigation water may help improve oxygen availability in the root zone. However, the benefit depends on the initial oxygen concentration, the rate of oxygen consumption, drainage conditions and the characteristics of the growing medium.

A study published in Science of the Total Environment in 2023 investigated oxygen and nitrogen nanobubbles in relation to tomato germination, early growth and soil properties. Under the study's experimental conditions, oxygen nanobubbles increased seed germination by approximately 10% and improved selected early-growth measurements by 30–50% relative to the control.

These findings provide evidence that nanobubble treatments can influence plant development under specific experimental conditions. They should not be interpreted as a guaranteed yield increase across different crops or commercial growing environments.

3. Effects on soil chemistry and nutrient availability

Plant nutrition depends not only on the quantity of fertiliser applied, but also on how nutrients behave in water and soil and how effectively roots can access them.

Dissolved oxygen and oxidation-reduction potential are important environmental variables that can influence chemical reactions and microbial processes in soil. Changes in these conditions may affect nutrient transformations and the release or availability of certain elements.

A 2022 study published in ACS Agricultural Science & Technology examined the effects of water containing different gaseous nanobubbles, including oxygen, nitrogen, hydrogen, carbon dioxide and air, on soil properties and nutrient release.

The researchers found that the effects differed according to the gas used. Oxygen nanobubbles increased dissolved oxygen and redox potential in the treated soil, while other gases produced different effects on nutrient release.

This distinction is important. Nanobubble treatment should not be assumed to produce the same result in every soil or with every gas. Nutrient availability remains dependent on soil chemistry, mineral composition, pH, salinity and other interacting factors.

For agricultural operations, the practical question is whether a particular treatment produces a measurable improvement in nutrient availability or uptake under the conditions present at the site.

4. Water infiltration, salinity and irrigation performance

Water must move through soil or growing media in a way that provides adequate moisture to roots while allowing appropriate drainage.

Compaction, water repellency, soil texture and elevated salt concentrations can complicate this process. In affected soils, improving irrigation performance may require a combination of water management, soil amendments, drainage and other site-specific interventions.

Nanobubble technology has been investigated for its potential influence on water infiltration and the movement of salts through the root zone.

A published Moleaer customer case study at Maricopa Orchards in California reported improved water infiltration and salt leaching following the installation of an oxygen nanobubble system. The case study reported an improvement in infiltration depth of approximately 20 inches compared with its control and salt leaching to depths of up to 46 inches.

These are results reported for a particular agricultural installation, not universal performance figures. The underlying soil conditions, irrigation practices, monitoring methods and other relevant variables must be considered when interpreting the outcome.

In saline soils, salt removal also depends on sufficient suitable-quality water, effective drainage and the movement of dissolved salts away from the root zone. Nanobubble treatment does not replace these requirements.

5. Root health, microbial activity and plant performance

The root zone is a dynamic environment in which plant roots, water, nutrients, soil particles and microorganisms interact.

Oxygen availability can influence the balance of microbial processes in this environment. Improving aeration may support aerobic biological activity, although the resulting microbial response depends on the existing ecosystem and the availability of suitable substrates and nutrients.

Research into nanobubble irrigation has examined potential effects on root development, nutrient uptake, plant biomass and resilience to environmental stress.

In the 2023 tomato study, oxygen nanobubble treatment was associated with changes in plant growth and leaf peroxidase activity. The researchers investigated these responses as potential mechanisms involved in plant development.

Separately, a 2026 study published in Agricultural Water Management examined oxygen, carbon dioxide and nitrogen nanobubble irrigation in lettuce. Its findings indicated that responses differed according to the gas and concentration used, with selected treatments improving growth-related outcomes and water-use performance under the experimental conditions.

Together, these studies suggest that the effects of nanobubble irrigation extend beyond simply increasing the oxygen content of water. They also demonstrate why gas type, concentration and growing conditions must be evaluated rather than assuming that all nanobubble treatments will have equivalent effects.

6. What do the reported agricultural results tell us?

Technology-provider case studies offer useful examples of how nanobubble systems have been applied in commercial agriculture. They can help identify outcomes worth investigating, but their reported results should be distinguished from independently replicated scientific evidence.

Moleaer's published agricultural material reports outcomes involving crop yield, root development, pathogen levels, irrigation-system hygiene and input use. Its published summary of a Delphy Research Institute strawberry trial, conducted in the Netherlands in 2020, reports a 14% increase in yield and a 74% reduction in Pythium counts in the nanobubble-treated group.

The provider's account describes a comparison between a control group maintained at approximately 7–9 mg/L dissolved oxygen and a treated group averaging approximately 30 mg/L dissolved oxygen.

This is a useful example of a measured treatment comparison. However, the result should be interpreted within the trial's specific conditions, including its crop, growing environment and oxygen-treatment regime. It should not be presented as proof that every nanobubble installation will deliver the same outcome.

For any commercial application, the most relevant evidence is the performance achieved under conditions comparable to those of the intended site.

7. How should nanobubble technology be evaluated?

A robust evaluation begins with a clear understanding of the problem to be addressed. The appropriate performance indicators should be established before installation or treatment begins.

Depending on the application, a site assessment and monitoring programme may include:

• Water quality: dissolved oxygen, pH, electrical conductivity, temperature and relevant chemical parameters.

• Soil and growing media: moisture content, infiltration, compaction, salinity and drainage characteristics.

• Plant performance: root development, biomass, crop quality, disease incidence and marketable yield.

• Irrigation infrastructure: emitter blockage, biofilm accumulation, maintenance frequency and cleaning requirements.

• Resource efficiency: water consumption, fertiliser use, chemical inputs, energy demand and operating costs.

Where practical, treated and untreated areas should be compared using an appropriate experimental design. Crop variety, irrigation volume, nutrient programme, environmental conditions and other important variables should be controlled or documented.

Measurements should be collected over a period suitable for the crop and the outcome being investigated. Baseline data, replication and transparent reporting are essential for distinguishing treatment effects from normal variation.

This approach allows the technology to be assessed on measurable performance rather than assumptions or isolated results.

8. The Blue Planet South Africa perspective

At Blue Planet South Africa, we believe environmental and agricultural technologies should be evaluated according to the problems they are intended to solve, the scientific evidence supporting their application and the results achieved in practice.

Nanobubble generation may offer value where dissolved oxygen, water quality, root-zone conditions or irrigation-system performance are limiting factors. However, its suitability must be established in the context of the specific water source, crop, growing medium and operating requirements.

Our approach is to connect scientific understanding with practical assessment. This means identifying the relevant constraints, establishing a baseline, selecting appropriate interventions and determining how performance should be monitored.

The goal is to support informed decisions about water management, resource efficiency and environmental performance.

Conclusion

Nanobubble technology is an active area of research in agricultural water management. Published studies indicate that the type of gas introduced, its concentration and the characteristics of the soil or growing system can influence plant growth, soil chemistry and nutrient-related processes.

Commercial case studies also report promising outcomes in crop production, root health, irrigation performance and salinity management. These results provide useful evidence of potential applications, while highlighting the importance of site-specific assessment and appropriate measurement.

The central question is not whether nanobubbles are beneficial in every situation, but where, why and under what conditions they deliver a measurable improvement.

For agricultural operations seeking to improve irrigation performance or investigate advanced water-treatment technologies, a scientifically grounded assessment is the logical starting point.

Explore the science. Measure the difference. Make evidence-led decisions.

Discuss an application with Blue Planet South Africa

If your operation is experiencing irrigation-water quality challenges, poor root-zone conditions, salinity issues or inefficient water use, contact Blue Planet South Africa to discuss your requirements and determine whether a site-specific assessment would be appropriate.

Contact us to discuss your water-management requirements.