What is Foliar Spraying?

Foliar spraying is when herbicide is diluted at a specific rate with water and spayed over the targeted plants to the point of runoff. An effective approach to weed control, foliar applications are the most common methods of herbicide application.

Best suited to plants where complete coverage can be achieved, optimal timing is one the key considerations that leads to more effective control. Ideal weather conditions such as calm winds, sun, and no rain ensure efficiency and effectiveness while helping to minimise off-target drift. Another critical aspect is herbicide selection. It is essential to choose an appropriate herbicide based on the types of weeds present and desired level of control.


There are several foliar application methods, including:

Low Volume Spraying
Using low pressurised equipment, such as knapsack sprayers, this method is close-range and allows for good coverage of weeds while minimising drift. Suitable for low growing grasses and plant species, you can treat weeds in any type of terrain accessible by foot. Commonly used in situations where precise weed targeting is required, herbicide usage is reduced making this a cost-effective option for the right situations.


High Volume Spraying
With this method high volumes of herbicide are applied with a pump powered spray unit. Hoses are connected to pumps that deliver the herbicide solution to the handguns at a higher pressure. Suitable for larger weeds and extensive infestation management, this method allows for greater spraying distance when compared to the low volume approach while also offering greater coverage and efficiency across larger areas. However, the risk of off-target damage is increased with greater potential for spray drift.


Boom Spraying
A widely used approach, boom spraying involves a multi-nozzle boom set up on either a utility vehicle, tractor, or purpose-built spray rig. Multiple spray nozzles are arranged in a row across the width of the boom for uniform distribution. Suitable for large infestations of low growing weeds, areas such as pastures and crop fields are ideal for this method. When setting up a boom spray it is important to consider boom length and height, selection of nozzle size, ground travelling speed, and if it is shrouded or unshrouded. With various set up styles, accurate traveling speeds and coverage needs to be maintained alongside regular nozzle checks to prevent blockages and ensure full coverage of the area.


Splatter Guns
Making use of a specialised nozzle that produces large droplets at high concentrations, this method involves low volume herbicide application. Splatter guns offer precise control as only a small section of the targeted weed’s foliage needs to be covered, minimising off-target damage. Suitable for areas with difficult access, it is traditionally used with selective herbicides.


Efficiently managing weeds while minimising unwanted environmental impacts relies on the right selection of appropriate herbicide application techniques tailored to the specific weeds and environmental conditions. By choosing the right method and following best practices you can effectively control your weeds.

Leave a Reply

Your email address will not be published. Required fields are marked *