How to use Garlon® 600


Garlon® 600 Herbicide

Garlon 600 Herbicide contains the active ingredient triclopyr, which has activity on a wide range of broadleaf weeds. It is registered for the control of woody weeds and melons as specified in the Directions of Use. Garlon 600 offers a solution for more sensitive weed control situations.

Garlon 600 – overview

Product key features

  • A foliar spray option for tough-to-kill woody weeds and many noxious herbaceous weeds.
  • Acts rapidly on weed foliage to provide quick browning of leaves and stems.
  • Leaf brownout and distortion of stem tips will normally be obvious within three days of application.
  • Short residual life in the soil allows planting of sensitive crops and shrubs soon after application.
  • Provides less risk of root uptake from desirable plants (physical spray drift can still cause damage).
  • Controls the target weeds without harming grass pastures.

Product description

Containing one of the three active ingredients in Grazon Extra, this product offers a solution for more sensitive weed control situations where root uptake (off-target damage) by desirable plants is a potential risk.

Garlon 600 has a short residual life in the soil and has a quick brownout of labelled weeds; but does not offer residual control of new germinations.

Product specifications

  • Ingredient:

    600 g/L triclopyr

  • Formulation:

    Emulsifiable concentrate liquid

  • Pack sizes:

    1 L, 5 L and 10 L

Major weeds controlled

  • African boxthorn control
  • Blackberry control
  • Broom control
  • Eucalypt regrowth control
  • Gorse control
  • Prickly pear (cacti) control
  • St John’s wort control
  • Wattle regrowth control

Woody Weed Control Guide


Use the controls at the bottom of the page to get the most from this useful new tool from the Woody Weed Specialists.

Find out more

Garlon 600 – application

Application methods

Apply as a foliar spot spray to completely wet all leaves and stems. Coverage should be to the point of run-off in that the chemical mix is just beginning to drip from the leaves once the spraying is completed. Think of painting a wall and use that motion in your spray action to achieve full coverage of the foliage, then use a more directed stream to thoroughly treat the stems and canes.

This type of application is called high volume spraying as you are applying a large amount of spray mixture to the target weeds. Provided that good coverage of the target weed is possible, high volume spraying can be completed using a variety of equipment – from a small hand pump unit to a knapsack sprayer through to a large motorised pump and hand gun unit.

With a foliar spray you are looking to capture enough chemical on the foliage to kill not only the above-ground portion of the weed but all of the root mass as well, so good coverage is essential. If you are spraying very large weeds like blackberries that are several years old, ensure that canes on the inside as well as the outside of the foliage mass receive direct contact with the applied spray.

As a guide, one hectare of blackberries 1–2 metres in height will typically require a spray volume of 3000–4000 litres to be thoroughly covered, whilst the same area of a small herbaceous weed such as ragwort will require 500–1000 litres.

A video demonstrating the correct techniques for high volume spraying can be accessed here.

Equipment required for application

  • Depending on the size of the job at hand:
    • Large dense infestations (for example large old dense blackberry stands) are best treated with a large motorised pump and hand gun unit. This equipment can often be hired or a contract spray applicator can be engaged.
    • However, a suitable knapsack or hand pump spray unit will suffice in many situations, provided that good coverage can be achieved (to the point of run-off).
    • Ideally use a spray unit that is dedicated for application of herbicides only (to avoid cross contamination).
  • Measuring jug.
  • Cotton overalls or long-sleeved shirt and long pants.
  • Washable hat.
  • Elbow-length nitrile/neoprene gloves.

Application timing for best results

In general, smaller weeds are easier to control than large ones.

Garlon 600 is most effective when applied to weeds that are not stressed due to lack of moisture, excessive heat, insect damage, etc. and are actively growing. Actively growing weeds will draw the chemical into the vascular system and transport it through the stems and down to the roots to ensure maximum efficacy.

A general guide to the best time of the year to treat common woody weeds can be found in this table.

Garlon 600 needs to penetrate into the leaves of treated weeds before any rainfall occurs so do not make applications if rain is possible before the spray is completely dry – usually one hour. Similarly, avoid application if the leaves are wet from rainfall or dew.

Once the weeds have been sprayed, leave them undisturbed so that the chemical is able to move throughout the leaves, stems and roots and provide complete kill. Disturbing the weeds by slashing, burning, mulching, etc. before the chemical is fully distributed will compromise the control achieved. We recommend that blackberries and other woody weeds not be disturbed for six months after spraying to maximise the performance of Garlon 600.

Application rate

For most weeds the rate of Garlon 600 to apply is between 170 and 340 mL per 100 litres of water.

Always check the label for the correct rate. A copy of the label can be accessed here.

Correct mixing procedure

If possible, mix Garlon 600 with clean water sourced from town supply or a rain water tank, although any source of clean water may be used. Avoid using water that is particularly ‘hard’ or strongly alkaline as that may reduce herbicide efficacy. Half fill the spray tank with water then add the Garlon 600 before adding the remainder of the water. If the product label requires the addition of a spray oil, penetrant or wetting agent to assist in control your particular weed population, mix in once the spray tank is full.

Once mixed, the spray solution should ideally be kept agitated and used immediately. However, if circumstances conspire to interrupt spraying, a mixture of Garlon 600 and water can be stored for up to seven days, provided that it is intermittently agitated each day, and well agitated again before use.

Garlon 600 – safety

Safe handling

Garlon 600 is classed as a Poison and must be kept out of the reach of children.

The product can irritate the eyes and skin, particularly in the concentrated form, so take care when measuring it out and adding it to the spray tank. If any does splash into your eyes or onto your skin, wash immediately with clean water.

Wear suitable protective clothing when measuring out the product and when spraying, such as overalls or a long-sleeved shirt and long pants along with a washable hat and elbow-length nitrile/neoprene (rather than PVC) gloves. Wash all clothing after use. Safety glasses or face shield are not specified on the label.

A copy of the Safety Data Sheet can be accessed here.

Safety to stock

There is no grazing withholding period for stock feeding in pastures in which woody weeds have been sprayed with Garlon 600.

However, care does need to be taken because some treated weeds often become very palatable to stock, as there is an increase in the plant’s sugar content as it dies, and stock will preferentially graze on these over the pasture grasses. If naturally toxic weeds such as ragwort, variegated thistle and capeweed are being sprayed, stock should be kept from the paddocks until these weeds have died.



Impact of Garlon 600 on the environment

Health and safety profile sheet

Many desirable crops and ornamentals are very sensitive to Garlon 600 so care must be taken when applying the product to ensure that there is no spray drift on to desirable plants or soil containing roots of desirable plants. A light but steady breeze directing any spray mist away from desirable plants is the ideal spraying condition. Avoid application when the wind direction is towards desirable plants or there is no breeze at all. In seemingly still conditions, spray mist can drift for long distances and in many directions, which can cause plant damage when it settles.

Plants susceptible to Garlon 600 include fruit trees, grape vines, legumes (pea, beans, lucerne etc.), potatoes, roses, shade trees and tomatoes.

Garlon 600 may be used around waterways but spray should never be applied to water, or soil within a dry water course, or allowed to drift into or drip off treated foliage into water.



Cleaning spray equipment

After spraying is complete, thoroughly clean the spray unit to ensure no residues remain that may cause damage to desirable plants when the equipment is next used. Empty the spray unit completely and drain the whole system. Wash the tank, pump, lines, hoses and nozzles with a mix of water and an alkaline laundry detergent such as Omo® or Drive®. Reassemble the unit, half fill with clean water and circulate through the pump and hose. Drain and repeat the rinsing procedure.

Ensure rinse water is disposed onto a designated area or an unused area where there is no risk to desirable plants.