Diatomite & Science: How a Geothermal Biomineral Supports Soil and Crops

What Is Diatomite?

Diatomite is a naturally occurring, highly porous sedimentary rock formed from the fossilised remains of diatoms – microscopic single-celled algae that lived in ancient lakes and seas millions of years ago. These tiny organisms built their cell walls from silica extracted from the water around them, and when they died, their silica-rich skeletons accumulated on the lake or sea bed, layer upon layer, eventually forming thick deposits of what we now call diatomite.

What makes diatomite particularly interesting for agriculture is its amorphous (non-crystalline) silica content. Unlike crystalline silica, which is dense and inert, amorphous silica is extremely porous, lightweight and highly absorbent. This unique structure gives diatomite a vast internal surface area – sometimes exceeding 30 square metres per gram – making it one of nature's most effective materials for holding water, air and nutrients.

Diatomite has been used for decades in industrial applications such as filtration, absorbents and even as a mild abrasive in toothpaste. More recently, agronomists and soil scientists have recognised its potential as a soil improver and natural source of plant-available silicon, particularly in soils that are degraded, sandy or intensively farmed.

Diatomite in Agriculture: Plant-Available Silicon

Silicon is the second most abundant element in the Earth's crust, yet it is not classified as an "essential nutrient" in the same way as nitrogen, phosphorus or potassium. However, a growing body of research shows that silicon can play a significant supporting role in plant health, particularly when crops are under stress from drought, salinity, disease or physical damage.

When diatomite is incorporated into soil, it can:

• Improve soil structure and aeration – the porous particles create tiny air pockets that help roots breathe and water move more freely.
• Enhance water retention whilst maintaining drainage – diatomite can hold several times its own weight in water, yet its open structure prevents waterlogging.
• Slowly release soluble silica that plant roots can absorb and use to strengthen their tissues.

Once absorbed by the plant, silicon is transported to the shoots and deposited in cell walls and the spaces just beneath the leaf cuticle. This deposition creates a physical reinforcement that can make stems more rigid, leaves more resistant to wilting, and the entire plant better able to cope with environmental challenges.

The Science Behind Silicon and Plant Performance

Research into silicon and plant performance has expanded significantly over the past two decades, with studies conducted on a wide range of crops and soil types. Whilst results vary depending on the crop, soil conditions and climate, several consistent themes have emerged:

1. Mechanical Strengthening

Silicon deposition in plant tissues can increase stem rigidity and improve the physical structure of leaves and stalks. In cereal crops such as wheat, barley and rice, this can help reduce lodging – the tendency for plants to fall over under the weight of grain or during heavy rain and wind. Stronger, more upright plants are easier to harvest and often produce higher-quality grain.

2. Stress Mitigation

Silicon has been shown to help plants cope better with a range of abiotic stresses, including:

• Drought – silicon can improve water-use efficiency and help maintain turgor pressure in leaves.
• Salinity – silicon may reduce the uptake of sodium and help protect cell membranes from salt damage.
• Heavy metals – silicon can bind with toxic metals such as aluminium and cadmium, reducing their availability to the plant.
• Temperature extremes – both heat and cold stress can be moderated by silicon's effects on cell wall integrity and water relations.

It is important to note that the degree of benefit varies widely depending on soil type, weather patterns and the crop's natural ability to accumulate silicon. Effects are often most pronounced in silicon-accumulator crops such as rice, sugarcane, wheat and barley, but other crops can also respond positively under the right conditions.

3. Disease and Pest Resilience

One of the most intriguing aspects of silicon nutrition is its potential to reduce disease and pest pressure. When silicon is deposited beneath the leaf cuticle, it forms a physical barrier that can make it harder for fungal pathogens to penetrate the leaf surface and for insect pests to pierce plant tissues. This is not a chemical defence, but rather a mechanical one – a kind of natural armour that complements the plant's own immune responses.

Studies have shown reductions in diseases such as powdery mildew, rice blast and leaf spot, as well as lower feeding damage from aphids, leafhoppers and caterpillars. However, silicon is not a substitute for integrated pest management or fungicide programmes; it is best viewed as one tool among many for supporting crop resilience.

4. Nutrient Interactions

Silicon can influence the uptake and distribution of other nutrients within the plant. For example, it has been shown to:

• Improve the efficiency of phosphorus use in some soils.
• Reduce the toxic effects of excess aluminium and manganese in acidic soils.
• Support better nitrogen metabolism under stress conditions.

These interactions are complex and not yet fully understood, but they highlight the fact that silicon does not work in isolation – it is part of a broader network of soil and plant processes that together determine crop performance.

Geothermal Diatomite: What Makes It Different?

Not all diatomite is the same. The quality, reactivity and bioavailability of the silica in diatomite can vary significantly depending on where and how it was formed. One particularly interesting type is geothermal diatomite, such as the deposits found in Turkey and used by Agri-Talya.

Geothermal diatomite has been exposed to natural heating and mineralisation processes deep within the Earth's crust. This geothermal activity can alter the structure and chemistry of the diatomite, often resulting in:

• Higher amorphous silica content – the silica remains non-crystalline but becomes more reactive.
• Greater surface area and porosity – the internal structure becomes even more open and absorbent.
• Enhanced bioavailability – the silica is more readily dissolved and taken up by plant roots.

For UK soils – particularly light, sandy soils or intensively farmed fields where silicon may have been depleted over time – geothermal diatomite can offer a more effective source of plant-available silicon than standard diatomite or other silicate minerals.

Agri-Talya sources its diatomite from geothermal deposits in Turkey and processes it specifically for agricultural use, ensuring consistent quality and particle size distribution. You can explore more about geothermal diatomite and see how Agri-Talya uses this resource here.

Diatomite and Modern Agronomy: Three Pillars of Evidence

Agri-Talya's approach to diatomite-based soil improvement is built on three pillars of evidence, ensuring that recommendations are grounded in science rather than marketing hype:

1. Peer-Reviewed Research from Around the World

Published studies on diatomite, silicon nutrition and related soil amendments have demonstrated a range of benefits, including:

• Improved soil water retention – diatomite can help soils hold moisture for longer, reducing irrigation needs and supporting crops during dry spells.
• Better soil physical condition – the porous structure of diatomite can improve aeration, reduce compaction and support healthier root development, particularly in degraded or stressed soils.
• Enhanced crop resilience – silicon from diatomite has been shown to support plant performance under drought, salinity, heat and disease pressure in controlled trials and field experiments.

Agri-Talya's protocols are designed to align with this body of research, focusing on practical, evidence-based applications rather than simplistic claims or miracle solutions.

2. Multi-Year Field Work and Farmer Experience

Laboratory research is essential, but real-world farming is where theories are tested. Multi-year field trials in Turkey and other regions have shown that diatomite-based soil improvement programmes can contribute to:

• More stable yields under variable weather conditions.
• Improved crop quality, particularly in terms of stem strength, disease resistance and stress tolerance.
• Better soil structure and water-holding capacity over time.

However, it is crucial to understand that outcomes depend on soil type, climate, crop choice and overall farm management. Diatomite is not a standalone solution; it works best when integrated into a holistic soil health strategy that includes appropriate nutrition, organic matter management and good agronomic practice.

3. Independent Agronomy and On-Farm Validation

Agri-Talya actively encourages independent agronomists and growers to trial diatomite-based programmes on their own farms and share their findings. This includes:

• Running side-by-side comparison strips to measure differences in soil moisture, silicon levels, plant health and yield.
• Collecting data on soil physical properties, water infiltration and root development.
• Sharing both positive and negative results to refine protocols and improve recommendations.

This commitment to transparency and continuous improvement ensures that Agri-Talya's approach evolves with new evidence and real-world experience, rather than relying on fixed formulas or outdated assumptions.

How Growers and Gardeners Might Use Diatomite

Diatomite can be used in a variety of agricultural and horticultural contexts, typically as a soil improver or soil amendment rather than as a fertiliser or pesticide. Common applications include:

• Improving light, sandy or degraded soils – adding diatomite can help these soils hold more water and nutrients whilst maintaining good drainage and aeration.
• Supporting crops prone to lodging or stress – cereals, grasses and other silicon-accumulator crops may benefit from the mechanical strengthening and stress mitigation effects of silicon.
• Enhancing overall soil health – diatomite can be part of a broader strategy to improve soil structure, support beneficial microbial activity and build long-term resilience.

Important: Always follow the product label and consult a qualified agronomist or adviser before changing your nutrition or soil management programme. Results will vary depending on your soil type, climate and farming system, and diatomite should be viewed as one tool among many for supporting soil and crop health.

To see how geothermal diatomite is used in practice and explore the range of soil improvers available, visit Agri-Talya's product collection.

Conclusion: Diatomite as a Tool for Soil Stewardship

Diatomite is not a miracle cure or a quick fix for poor soil management. It is, however, a science-backed, environmentally responsible soil improver that can play a valuable role in supporting soil health and crop resilience when used thoughtfully and in the right context.

By providing a natural source of plant-available silicon, improving soil physical properties and supporting crops under stress, diatomite can become one of the tools that growers use to build more resilient, productive and sustainable farming systems. The key is to approach it with realistic expectations, a commitment to good agronomy, and a willingness to learn from both research and on-farm experience.

Agri-Talya is committed to advancing the science of diatomite-based soil improvement through research, transparency and practical protocols that work in real-world conditions. Whether you are a commercial grower, a market gardener or a home enthusiast, understanding the science behind diatomite can help you make more informed decisions about how to care for your soil and support your crops.

Read more about diatomite & science at Agri-Talya, or discover more insights on the Mezetto journal.