What is Hydromulching?
Hydromulching is a vegetation process that involves spraying a slurry of water, seed, fertiliser, cellulosic mulch, tracking dye, and a binder/tackifier on damaged and depleted soils to provide fast, economical and efficient revegetation.
The mixture sprayed from a specially designed hydroseeding truck is kept agitated during the application, ensuring even coverage.
The cannon sometimes referred to as boom, attached to a hydroseeder is capable of spraying the mixture over 100 metres. These cannons enable coverage in even the most difficult to reach areas.
Benefits of Hydromulching
The addition of mulch into the hydromulching slurry is what primarily differentiates it from hydroseeding. There are several reasons why including mulch in the mixture, instead of water as is the case in hydroseeding, is preferable.
Minimises Moisture Evaporation
Hydromulching creates a healthier, more sustainable, and ideal environment for the sprayed seeds. The mulch itself acts as a hydraulic growth medium and provides a protective cover and moisture reservoir for the seeds. The roots of the seeds can burrow deeper into the soil, preventing them from getting run off by water as they are still in the process of germinating.
Prevents Birds from Damaging Crops
It is not only water and soil erosion that threatens the likelihood of the sprayed seeds from taking root. Depending on the natural ecosystem of your site, bird species may also become prey to these fragile grass crops.
The thickness of the mulch in the formulated mixture acts as a protective layer and stops birds from getting to the seeds before they sprout. As a result, this reduces the amount of waste – in all aspects relating to the application.
Protects Seeds from Wind Erosion and Water Runoff
When using mulch in combination with a binder/tackifier, the fibres will stick together and “hold onto” the ground. This surface cover provided by the fibres works to stop the wind from picking up dust and displacing the seed. The fibres also protect the seeds from rain and water run-off that commonly hinders growth due to the eroding topsoil.
Covers Large and Difficult Areas
Hydromulching is an effective and viable option for vegetating vast expanses of land quickly and easily. The types of terrain can range from steep batters, part of verges, and flat properties, to areas that are hard to access or significantly sloped.
Hydromulching Promotes Quicker Growth
One of the main benefits of hydromulching is the speed of growth. The medium for plant growth that is introduced by the hydromulching slurry applied encourages seed germination. It locks down the topsoil through the protective cover it creates, thereby ensuring the seeds take root, germinate, and eventually vegetate.
It’s not unusual to see significant growth within a few weeks which, during the early stages of germination and growth, can provide much relief to the landowner.
Suitable for Varied Applications
Experts highly recommend hydromulching for vast expanses of land that have sections with limited access. It is ideal for erosion control and stabilisation of steep banks like roadside batters, soil stockpiles, and even awkward slopes of creeks and drains. It is also suitable for long-term dust suppression, mine site rehabilitation and remediation of large industrial areas.
How It Works
The process of hydromulching involves spraying a slurry mixture composed of water, seed, fertiliser, cellulosic mulch, tracking dye, and a binder/tackifier using a specially designed hydroseeding truck. These hydroseeders keep the mixture continuously agitated during the application, which ensures an even and uniform application.
A cannon also referred to as a boom, may alternatively be used to apply the slurry mixture, when the type of terrain calls for it. These cannons are capable of spraying mixture to over 100 metres more than hydroseeders, which is ideal in accessing areas that are difficult to reach.
It is worth noting, though, that it is crucial to investigate the state of the site’s soil even before conducting the hydromulching process. Doing so not only eliminates the risk of uneven plant growth, but this also reduces the possibility of pest infestation.
The site needs to be prepared, cleared of weeds, stumps, rocks, or any other debris that may be lurking deep underneath the ground. Once the initial site preparation is completed, only then can the hydromulching process commence. By this time, a plan will already have been tailored to the site using the initial soil analysis conducted, thus, providing a suitable approach to guarantee results.
After Application Maintenance
Your designated environmental specialist should know when the most suitable time to conduct the hydromulching project is.
Several factors, such as your weather conditions, dictated primarily by the state or region your site belongs to, as well as the likelihood of rainfall, and the average range in your site’s temperature, will affect the course of action to take during the hydromulching application.
If the timing of the application of the hydromulching mixture is during the most appropriate season, there will be very little after-care maintenance required. Typically, natural rainfall will provide proper water filtration. However, if the site location usually does not produce much rain, this may cause the drying out of the mulch, thus, adversely affecting seed germination.
There are numerous types of mulch available in the Australian market today, all with their benefits. Find out more information about the various mulches on offer and which one may be suitable for your project goals.