Frequently Asked Questions

1. Which crops has SafeRock® proved to be very effective in?

Trial results for wheat, rice, cotton and maize crops confirm the many benefits of using SafeRock®. The practical benefits include:

Increased crop yield – trial results against inorganic fertiliser use alone include: Wheat +28% yield, Rice +21.2% yield, Maize +53.4% yield

Improved long term soil quality - SafeRock® is not water soluble and so is not leached from the soil. Repeated applications build up the available nutrient status and soil organic carbon levels. Soil analysis within the wheat trial showed an increase in soil organic carbon of 41% following the use of SafeRock®.

Decreased chemical fertiliser input costs - the rice trial showed reduction of fertiliser use by 25% with same yields obtained; the maize trial showed reduction of urea by 50% with same yield obtained.

Improved quality and nutritional value of produce - the wheat trial tissue analyses also demonstrated improved quality and nutritional values with wheat grain calcium increasing by 29%, magnesium by 63%, and numerous trace mineral increases over the control crops. In subsequent rice and maize trials, the produce was again found to be higher in the vast majority of nutrients tested. More nutritious produce leads to better flavour, quality and can achieve higher prices at sale. More nutritious produce also benefits the consumer, whether human or farm animal, by passing on its higher mineral content thereby helping to avoid potential dietary nutrient deficiencies and aiding healthy growth and development.

2. SafeRock® does not have a high NPK (Nitrogen, Phosphorous and Potassium) value. How can it be useful to the soil?

Plants require many types of nutrients to grow healthy and nutrient rich crops. In addition to the macro-nutrients (some P and K), SafeRock® also supplies a range of other micronutrients and trace elements (e.g. S, Ca, Mg, B, Si, Cl, Cu, Fe, Mn, Zn) which are essential for healthy plant growth and development. Agricultural soils that are supplied only urea or NPK fertilisers are often depleted in these trace elements, leading to lower yields and poorer nutrient concentrations in produce. In addition, SafeRock® contains valuable clay minerals that attract and hold nutrient cations such as ammonium, potassium, magnesium, calcium and other trace minerals, ready for uptake by the plant root systems. The clay minerals reduce soil nutrient leaching which increases fertiliser efficiency and crop yields.

3. There are no high values of minerals in SafeRock®. Some soils already have these minerals what is the additional advantage of SafeRock®?

SafeRock® chemical composition and mineral content is unique and it is the proportional combination of these elements which gives its ability to supply plants with the minerals it requires, while also releasing other minerals previously locked up in the soil profile. Serious mineral deficiencies identified in soil should be treated directly with the mineral salt in question for fast remediation, but should be used alongside SafeRock® to increase its efficiency and ensure a long-lasting effect. The broad spectrum of trace minerals in SafeRock® helps to address any ongoing trace mineral deficiencies when applied regularly, and the clay minerals within SafeRock® attract and hold the trace elements ready for plant uptake.

Trial results (rice and maize trials 2015-16) consistently show SafeRock® outperforming single mineral supplements such as sulphur or zinc. Even though levels of some minerals seem low in SafeRock®, it is the increase in nutrient efficiency that drives higher and more nutritious produce.

Soil quality increases with repeat applications as the micronutrients and improved physical soil structure stimulates biota, biomass and organic matter content. Improvements in organic carbon and clay mineral content helps to hold water within the soil more effectively.

4. How does SafeRock® make the locked up minerals in the soil more plant available?

SafeRock® pH level being alkaline has a natural liming effect which assists the soil to move towards a balanced neutral pH level. As a result, more nutrients within the soil root zone become chemically available to the plant. SafeRock® contains numerous clay minerals which act as a nutrient store for these newly available, positively charged cations, like nitrogen-rich ammonium, potassium, magnesium and calcium, which are then released when needed by plants.

5. Would the content of heavy metals in SafeRock® endanger the environment and ecological balance of the soil?

SafeRock® will not affect the long term environmental integrity of the soil as its metals are in normal ranges for agricultural uses. It has been certified as suitable for use in organic agriculture as a mineral soil conditioner.

The UK authorities issue technical guidelines with regards to permissible heavy metal limits for agricultural land. This is based upon The Agriculture Regulations 1989, which enforce the provisions of the EC Directive 86/278/EEC on the protection of the environment, and in particular of the soil. These UK guideline limits are amongst the most stringent in the World. We have checked that the levels of heavy metals within SRM are well within these UK guideline limits. For example:-

EC Directive 86/278/EEC (mg/kg) SRM (mg/kg)
Arsenic 50 3.5
Cadmium 3 less than 0.05
Chromium 400 52
Mercury 1 less than 0.35
Lead 300 13

Heavy metals are present in ALL soils all over the world. They are unavoidable. SRM heavy metal levels are well within stringent guideline levels, and pose no long term risk to any soils.

6. How will SafeRock® reduce the application of NPK by up to 50%?

SafeRock® can be used to extend urea or NPK fertiliser efficiency and performance. Blending fertiliser with SafeRock® can produce the same yield with less fertiliser because of the reduction of volatilization and leaching losses. It is particularly suitable for banding under drip irrigation where it will assist water infiltration, distribution and retention. When fertigation is practiced it will actively hold the nutrients in the root zone. Most NPK fertilisers are highly soluble acid salts and much of the initial application can be lost via leaching and agricultural run-off, which then passes into freshwater surface and groundwater systems causing pollution to natural habitats and potential harm to human health.

7. How does SafeRock® stimulate earthworm activity?

The stimulation of earthworm activity is triggered by a combination of factors. Microbes and earthworms thrive in re-mineralised soil which as a result increases aeration, nutrient and organic matter processing, and water holding capacity. When SafeRock® is applied in combination with adequate moisture, soil carbon levels and a nitrogen source, earthworms feed upon the microorganisms and organic matter. Soil minerals and micronutrients are processed by the worms, whilst decomposing organic matter which make the minerals and nutrients available to plants and crops.

8. Can SafeRock® be mixed with NPK instead of other fillers or bulking like lime, quartz or sand?

SafeRock® can be used as a beneficial bulking agent to replace sand or other inert products in current chemical fertiliser production systems which have no agricultural value to soil or plants. Urea, NPK fertilisers or organic fertiliser sources can supply their nutrients much more efficiently, improving yields and reducing fertiliser application rates and costs. In numerous trials it has been shown that the farmer is able to reduce fertiliser inputs by at least 25% and still obtain the same yield. This can result in significant savings to the farmer.

9. How does SafeRock® address soil acidity?

With a moderately alkaline pH of 8.83 it can help decrease the acidity of acid soils, buffering soil pH, reducing the need for lime applications, and improving nutrient availability. In alkaline soils pH will be largely unaffected, as the alkaline soil effectively buffers the alkalinity of applied SafeRock®, but nutrient efficiency will be boosted by the improved cation exchange capacity of the soil following the addition of SafeRock®. It has a natural buffering effect on soil acidity and also on nutrient imbalances within the soil, e.g. high iron levels, which permits healthier root growth and plant development.

10. What makes SafeRock® different to other rock dust products on the market?

The key to understanding one of the main differences of SafeRock®, lies in its clay mineral content. While insoluble, it acts as a nutrient holding and exchange matrix due to its overall negative electrical charge. This clay mineral content is not present in many other mineral rock dusts, and is responsible for the nutrient efficiency gains seen when SafeRock® is used in practise.

This clay mineral nutrient exchange matrix allows the exchangeable cations within the soil, either naturally present or applied via fertilisers, to be attracted and held near the plant root zone rather than being leached away. The plant then drives its own nutritional needs by selective mineral uptake from the matrix. In turn, the renewed negative charge on the matrix surface attracts another cation (e.g. ammonium, potassium, calcium, magnesium, iron, as well as numerous trace elements) to replenish the vacant site. In this way, the insoluble clay mineral matrix allows plant-driven nutrition.

Many rock dusts available, e.g. basalt, granite, etc. are of volcanic origin. SafeRock® is different in that it is a sedimentary rock, rather than igneous or metamorphic. Having been through a long process of deposition, anaerobic digestion processes and compression, it should be in a form that is more easily broken down by plant root organic acids, microbiota, and physical & chemical weathering processes. The nutrients should be generally more accessible.

11. The complete analysis of SafeRock® shows around 70 elements present. Are they all required?

No. Seventeen elements have been identified that are required by higher plants – the macronutrients C, H, O, N, K, Ca, Mg, P, S, and the micronutrients B, Cl, Cu, Fe, Mn, Mo, Ni and Zn. Some additional nutrients are required for some plants or under particular environmental conditions e.g. Co, Na, Si.

Nutrients essential to plant life occur at various concentrations in different rock mineral sources, however, not all rock minerals contain all of the above plant required nutrients in a balanced composition. Although SafeRock® has around 70 minerals and trace elements, only seventeen are actually required by plants, the rest are of no benefit but are only present in trace amounts. With the exception of C, H, O (which plants can obtain from the atmosphere and a water source) and N which is not usually available in any significant quantity in any rock dust, SafeRock® contains every other required element necessary for healthy plant growth.

12. SafeRock® is insoluble. How are the micronutrients released for plant uptake?

Whilst SafeRock® is insoluble and provides a long-term benefit to soils, the mineral content within SafeRock® is released for plant uptake over time by numerous processes, from microbial and earthworm action, to plant root organic acids & natural physical and chemical weathering.

Depleted soils are inhospitable to soil microbiota and numbers decline. When a mineral-rich food source such as SafeRock®, is applied to the soil, microbiota and earthworm numbers rapidly increase. In feeding upon the inorganic minerals, they not only mobilise nutrients but also convert them into organic mineral forms. Through their own natural life cycles, these organic minerals are returned to the soil and made available for plant uptake. Plant roots also produce organic acids - this increases the local acidity around the root systems to directly mobilise nutrients from organic and inorganic sources such as SafeRock®. Over several years, the application of SafeRock® will eventually be consumed. We recommend annual applications of SafeRock® to ensure consistent performance from the micronutrient and clay mineral content of SafeRock®, and to build long-term soil quality.

Without SafeRock®

With SafeRock®