As part of one of our longstanding programs funded by Seqwater, we had the opportunity to trial a biostimulant to increase plant health and growth rates and more rapidly achieve our revegetation goals, especially in challenging areas. The team was impressed with the promising results, and it looks like this product will help boost our recipe for flood resilience and improved water quality.

		Cleaner water Containing and controlling erosion and sediment flowing downstream improves water quality.
		Flood resilience Stabilising gullies and reducing streambank erosion increases their resilience to erosion during floods.
		Protects agricultural and environmental values We are protecting agricultural land and environmental values by intervening to control gully and streambank erosion.

Our amazing team were recently in the field to check out the performance of a new addition to our revegetation process: a biostimulant.

The biostimulant was trialled on some of the Mid Brisbane Partnership Program sites to test whether it could be useful to speed up vegetation establishment on riverbanks and therefore achieve streambank stabilisation outcomes in minimum time.

The trial demonstrated promising results with improved growth rates and plant health observed across trial sites. In response, the team have decided to utilise the biostimulant across all other revegetation sites in the Program where rapid native vegetation establishment is critical to success!

Read below to learn more about it.

After the 2022 floods

Since 2017, Healthy Land & Water has been working with Seqwater on the Mid Brisbane Partnership Program aimed at reducing sediment entering the water source for the Mount Crosby Water treatment plants and building resilience in the Mid-Brisbane River for future floods.

Past flooding resulted in severely eroded gullies and streambanks, and without immediate intervention, these areas would continue to fail and deliver increased sediment into the Brisbane River.

Following the extreme flood events in 2022, some properties in proximity to Lowood and Mount Crosby water treatment sites have been identified by Healthy Land & Water and Seqwater for erosion repair works, with the rapid establishment of healthy vegetation vital to the success of these sites.

Revegetation and a biostimulant trial

On one property, erosion control involved utilising cement mat chutes, fencing, green engineering and revegetation, as a solution to repair and deliver resilience to these gullies during future flooding events.

Installing concrete mat chute in proximity to one of the eroded gullies.

After the installation of concrete mat chutes, we planted rows or “hedges” of Vetiver Grass which grows as dense clumps helping to slow down water flow and reduce its ability to erode soil.

It is on these Vetiver “hedges”, that we trialled a bio stimulant to test its value in promoting vegetation establishment and therefore achieve mass stabilisation outcomes in minimum time.

As part of the trial, we revegetated a control site using traditional methods with no bio-stimulant to compare to sites treated with biostimulant.

The results were very promising, as the site treated with the product appeared healthier and exhibited better root system development when compared to the plants in the control site.

Vetiver treated with biostimulant.

The biostimulant increases the rooting size and strength.

Encouraged by these findings, we decided to extend the trial across additional sites and look forward to seeing the results of these trials in time.

700 natives planted in 2 days!

We are excited and hopeful for this important addition to our approach to revegetation. Speeding up plant establishment could make a big difference in timeframes for revegetation, reduction of erosion risks and increased flood resilience.

What is a biostimulant?

Sometimes, nature might need support to perform optimally. Plant biostimulants do just that!

Plant biostimulants work to activate biological processes in the soil or within the plant, improving plant health by increasing soil nutrient availability, soil structure, root depth, water infiltration and water holding capacity.

In addition, biostimulants also improve plant tolerance including physical stresses on plants such as extreme temperatures, drought and salinity. Although it's impossible to entirely predict and prevent stresses, plants can be equipped with products like biostimulants to enhance their tolerance to these conditions.

We used a biostimulant that was microbially formulated to improve crop and soil health, soil structure, rooting depth, water infiltration and water holding capacity.

The Mid Brisbane Partnership Program: Addressing water quality, sediment flow and flood resilience

The Mid Brisbane Partnerships Program between Seqwater and Health Land & Water started in 2017 and, has entered a new five-year phase through to 2028. The program collaborates with landholders to deliver projects including riverbank revegetation, installing fencing, weed control, and stabilising gullies to protect water quality in the Mid Brisbane River.

This initiative is crucial as around 60% of South East Queensland’s drinking water passes through the Mid-Brisbane River before being treated at the Mount Crosby Water Treatment Plants. The catchment is vital for drinking water, irrigation, recreation, and amenity for residents and industry.

This restoration and water protection program is funded by Seqwater and delivered in collaboration with landholders.