BARRICADE® Herbicide Liquid formulation: Quick, Easy and Economical Weed Control for Production Nurseries

Product updates

We live in a world with more limitations on resources and ever-increasing time constraints, so the difficulty in finding ways to increase efficiencies in a production nursery is substantial. Especially in an environmentally conscious setting, when minimising the use of chemicals is desired.

Changing production methods or even agronomic programs within your production nursery programs can be daunting to consider and even more so to implement. But more often than not, once we make the decision to adopt a new and innovative technology, you’ll wonder why it took you so long to make the change. 

BARRICADE® Herbicide as a liquid is an innovative pre-emergent weed control technology with multiple benefits for production nurseries when you adopt it early on, such as:

Labour-saving: BARRICADE® is quicker and easier to apply when compared to pot by pot (manual) applications with granular formulations. When the liquid is applied it is done so in about 60% less time compared to granules.

Increases profitability: Using BARRICADE® is a more economical solution than granular products. Moreover, once the equipment is calibrated, it not only makes it easier than spreading granules manually, but it avoids over application due to better accuracy.

Longer lasting: Provides weed control for up to 4 months in potted plants, reducing the number of herbicide applications, and the associated labour. BARRICADE® will result in significant economical saving compared to the main brands of granule pre-emergent herbcides.

Lower environmental impact: BARRICADE® stays where it is placed.

Non-scheduled product: BARRICADE® leads to less toxicity exposure to staff and customers.

How to successfully switch your nursery to BARRICADE®?

The key part of switching your nursery from a hand-spread granule herbicide application to using BARRICADE® Herbicide is the proper calibration of the spray equipment and applicator. Once this is done, application becomes fast, effective and accurate. 

Check out this method of calibrating spray equipment, which can be easily replicated with any other type of spray equipment.


Sprayer calibration method

Sprayer calibration is essential to know the volume of spray mix – and consequently the application rate of products – being applied across a given area.

  1. Mark out an area 10 m x 10 m (100m2) on a surface typical of that to be sprayed

  2. Half fill the spray equipment with clean water. Place on a flat surface and mark precisely the water level with a waterproof pen. Be aware walking speed can vary considerably when carrying a full sprayer, compared to when empty

  3. Carefully spray the pre-marked area 

  4. Put the sprayer back on the flat surface and note where the water level is at completion of spraying treated area, i.e. , using a measuring jug, refill the sprayer back to the marked line. Sprayer was half full on 7 L prior to starting and is now on 2.2 L

  5. Meaning you have used 4.8 L of water to treat/cover 100m2.

  6. Refer to the BARRICADE® Application Chart below, which in this example will advise you to add 80 mL of BARRICADE® Herbicide for each 5 L of water in the spray equipment, which is equivalent to the highest label rate application. E.g – 10 L of water equals 160 mL of BARRICADE® being added or 20 L of water equals 320 mL of BARRICADE® being added to the tank.

Repeat the calibration process for different surfaces and terrains being sprayed.

TIP: Different operators will walk at different speeds; check calibration for each operator and instigate standard spraying practices (see overleaf). Also check the calibration for each different spray equipment; it can vary considerably between manufacturers and sprayers.

The critical part of any spray equipment calibration, is understanding the size of the area you are going to treat. Which will in turn, dictate the water and product volumes you will need to use.

BARRICADE® Application Chart


As a practical example, and using the table above, you have a total area of 100m2 to treat.  The minimum water quantity to add to the tank is 5 L as when applied evenly to the total area it ensures a good coverage across the surface.  The associated recommended rates then of BARRICADE® to add to the tank will be between 40 – 80 mL.  Use the higher rate if longer herbicidal activity is desired.

Essential Tips and Best Practices for BARRICADE® Application:

  • Calibrate first. This will give you confidence over how much product to add to the spray equipment tank to sufficiently cover all the required area.

  • Ideally the potting media should be moist, well balanced between saturation and dryness, which will allow it to accept the product molecule evenly when washed in after application.

  • Wash in afterwards with 2 or 3 mL of irrigation. This volume will effectively remove, the molecule from the surface whilst still remaining high in the soil profile where weed seeds will attempt to germinate and establish.

  • Pre-water plants the night before to ensure optimal weed germination protection. Then avoid any additional irrigation or rainfall for a 24-hour period. This facilitates the binding and locking of the BARRICADE® molecule onto the potting media particles, where it will remain and provide superior protection against weed germination.

By following these best practices, you can rest assured that your weed management is taken care of for up to four months, allowing you to be worry-free for a longer time!

Extra tip: get two jobs done at once

BARRICADE® Herbicide can be easily and quickly mixed in the same tank as glyphosate and applied at the same time to areas where the aim is to knockdown weeds as well as provides pre-emergent control for total nursery hygine.

This will not only reduce labour efforts and improving profitability, but will also decrease chemical usage and exposure of your staff, leading to more sustainable and responsible weed management practices and higher staff moral.


BARRICADE® Herbicide offers you:

  • One application provides up to six months control, and four months weed control in potted plants.

  • High plant safety with low risk of phytotoxicity or plant damage to desirable foliage or flowers.

  • Improved weed management program with increased productivity and sustainability, thus leading to higher profitability!

  • Exemption from poison scheduling.

  • A low-odor and non-staining formulation 

  • Broad-spectrum solution which can effectively control a wide range of grassy and broadleaf weeds, including African Lovegrass, Parramatta Grass, Summer Grass, Crab Grass, Crowsfoot Grass, and Winter Grass.

At Syngenta, we are committed to partnering with greenhouse and nursery growers to develop innovative agronomic solutions that result in beautifully strong, marketable ornamental plants. This commitment to success is strengthened by our pre-emergent herbicide BARRICADE® Herbicide which provides an effective and economical weed management solution for production nurseries.


For further information, please visit the Syngenta Ornamentals ANZ YouTube channel: 

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