Case Study: Biosmart Zeolite Plant Study
Background:
There are a number of new products on the horizon that should be of interest to many growers in Australia.
One of them is a natural mineral called Zeolite that can be tilled into the soil to provide truly marvellous
results. Zeolite is formed when volcanic ash recrystallises in the presence of water over millions of years.
The volcanic crystal then takes on some very interesting properties.
Firstly a honeycomb like crystal is created which allows Zeolite to trap water. This reduces water loss
through runoff and evaporation.
Secondly, Zeolite has a slight negative charge that attracts essential nutrients such as nitrogen and
phosphorus and holds them in the soil. The charge is strong enough to prevent water from washing the
nutrient away. In many ways Zeolite acts as a slow release fertilizer with a few very important differences:
1. Zeolite lasts in the soil up to 25 years.
2. Zeolite acts as an ‘activity site’ for beneficial bacteria in the soil that can remove nitrogen from the
air and that can break down nitrogen based products (eg urea).
3. The Roots of a plant can remove (through osmosis) the essential nutrients from the Zeolite when
the plant requires the nutrient.
Commonly in Australia zeolite is used as a filter medium for sewage effluent. A number of large councils in
Australia (Brisbane City Council being the largest) have purpose built Zeolite filters that are designed to
remove primarily nitrogenous wastes from treated Sewage effluent.
The strength of Zeolite lies in its ability to attract and bind nitrogenous and phosphorus based compounds
and thus markedly reduce the amount of fertilizer lost through run-off or leaching from the soil (a big plus in
reducing the frequency of algal blooms). From there on the picture becomes a little hazy with theories
abounding as to why Zeolite has such a positive effect on plant growth. It is thought that as Zeolite also
traps water it creates a site at which Bacteria tend to congregate. There is also a measurable increase in
the Cationic Exchange Capacity of the soil (particularly in poor quality soils) when Zeolite is added in
relatively small amounts (commonly 1-2 tons per hectare).
One of the more unusual findings from authorities whom have used Zeolite is that Zeolite tends to migrate
through the soil. Zeolite placed below the level of the plant’s roots tends to attract the roots and promotes
deeper root growth. Zeolite deposited just below the surface of the soil will be picked up and dragged down
through the soil by the growing plant root. The way the roots bind to the Zeolite is quite unusual. In many
instances the Zeolite cannot be removed from the root without damage to the root. As the root penetrates
deeper into the soil it tends to pull the Zeolite down with it. The net result is that plants seem to thrive when
small amounts of Zeolite are added to the soil. In addition the mineral itself can remain in the soil for up to
25 years so it is very cost effective.
Biosmart is trailing Zeolite as a filter medium for vegetable oil with one of Australia’s largest margarine
manufacturers. The study is to determine if the 'waste' filter medium can be used as an additive to animal
stock feed and then to use the waste from the stock as a soil enrichment product. Biosmart Zeolite has also
been applied to over 750 plants in a vineyard belonging to the McWilliams Winery in the Hunter Valley with
the aim to improve water retention and nutrient retention in the soil. Interestingly Darwin City Council has used Zeolite for a number of years. Other councils are currently investigating the cost savings Zeolite offers when used as part of the soil mix used for public gardens and works.
There is a great deal of detailed information on the Internet regarding the use of Zeolite to enhance poor
soils. At this time Zeolite in Australia is a relatively new product due to the fact that the discovery and mining
of commercial deposits is relatively recent. Whilst in the past certain people have used Zeolite in Australia it
was expensive as it was generally imported from overseas, commonly New Zealand. Given that the use of
Zeolite in the US is extensive there is very little doubt that we too will see its use expanded here in the next
few years.
Description of Photographs:
Following is a series of photographs that records the development of two tomato plants from seedlings.
Both plants were planted at the same time, however the soil mix of the plant in the brown pot (Plant A)
included half a cup of Zeolite.
At 5 week intervals the plants were photographed and on each occasion the tomato plant grown in the
Zeolite infused potting mix (Plant A) showed significantly more growth and developmentally was more
advanced. Measurements of the two plants also indicate that Plant A exhibited consistent rapid growth
whereas, the Plant B tended to grow in spurts. From weeks 10 – 15 Plant B has undergone a growth spurt
however it is still not producing flowers.
There is evidence that growth in chickens, pigs and cattle can also be enhanced using Zeolite as a feed
additive. In animals it appears that the Zeolites ability to absorb ammonia-based compounds improves the
animals ability to absorb digested food more readily. This is by no means a definitive study but rather a
case study to demonstrate that there is real potential for Zeolite to be used to enhance plant growth.
