General Info -


Rock minerals are widely touted as important soil improvers that with use will result in healthier and stronger plants.
But what are they and do they work?

The first time we ever used these products ourselves was years ago. We had planted some trees at the bottom of our block. They were root bound in their pots and way past due date for planting out.

Being extremely time-poor, we simply dug some holes with the augur and put them in and that was that.

The soil on this part of the block is sandy loam, with an emphasis on sandy, and little by way of organic matter.

The trees didn’t die but they didn’t really look that happy either.

We finally got around to doing something about it and started by using some rock mineral (in this case Earthlifes ‘Garden Mate’) and simply applied it around the drip zone of the trees and watered it in.

The response was startling, to say the least.

2 and 1/2 days and we started to see visual improvement in the trees.

Expectation was that at least it would be a couple of weeks before we saw anything of note. IF we saw anything of note.

Bear in mind, this was an extreme situation given the soil, but all the same, at that point we became believers.


Rock Minerals may come from different mined sources but all have similarities in that the specific ground rock used contains multiple minerals needed for healthy plant growth.

(You can’t just pick any old rock source and put it through the crushing process).

Those minerals in the ground rock are made plant available by beneficial soil microbes (fungi and bacteria).

Also, products like Earthlifes 'Garden Mate' contain high levels of plant available silica, an element that many believe has been largely overlooked when it comes to plant health but which has a significant role to play, especially in terms of disease/pest resistance and drought and frost tolerance.

Typically, expect to pay around $4-5/kg for your rock minerals.

We can only advise you on the use of Rock Mineral’s from a personal use/anecdotal perspective, but we have had excellent results over time and suggest that you trial some yourselves so you can form your own opinion.



*Microbial activity in the soil is a factor of, amongst other things, soil temperature and as such in winter when the soil temperature is low, microbial activity is reduced, and if cold enough, stops completely. Applications in winter are still beneficial though, because it helps contribute to the ‘pool’ of mineral available to the microbes once the soil temps start to rise in spring but don’t expect dramatic results such as we had on our trees during this time of year from it’s use.

Plus, the old adage of ‘results may vary’ applies here as it does with many things. Consider the early results with our trees (Native Franjipani) on sandy soil as an extreme example of the positive way a rock mineral can improve plant performance that may not be replicated to the same extent in every instance.


**Of the readily available products on the market here in South-East Queensland, I do find myself needing to point out that the ‘Rock Mineral’ as manufactured and marketed by Richgro is not all rock mineral.

On the bag you will notice under the main description ‘Rock Mineral’ is a secondary heading ‘Fertiliser and Soil Improver’

Based on the analysis and forms of nutrient supplied my best calculation is that this product is 75% fertiliser, 25% rock mineral.

Beware if you have plants with low nutrient/fertilising requirements such as succulents and cacti.

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