Grass-roots community organisation that aims to improve the natural condition of the Derwent catchment



The following page is a brief summary of information available on the DPIPWE website regarding Horehound control. For more information view here

Non-chemical control

Physical removal

  • Small infestations can be controlled by grubbing plants.


  • For dense infestations, the area should be burnt (to stimulate seed germination) and then ploughed to bury the plants. Alternatively un-rooted plants can be removed completely as partially buried plants can continue to grow.
  • Summer cultivation is preferred because the disturbed plants are readily killed by the heat of the sun.
  • Repeated cultivation is necessary to up-root any new Horehound growth, followed by sowing to crop or pasture.
  • Use a strongly competitive grass/clover mixture. In areas subject to drought or severe attack by pasture insects, either Phalaris or Cocksfoot should be included.
  • Spot spray any surviving Horehound in the new crop or pasture.
  • New pasture should not be grazed in its first year to give maximum competition with Horehound seedlings. Rabbits should also be controlled on the treated areas
  • Non-arable areas, such as stony ridges or sheep camps can be hand sown or sown through a fertiliser spreader after herbicide application.
  • Planting trees is another option where it is difficult to establish pasture.


  • Burn dense infestations to stimulate seed germination before cultivation.


  • Horehound infestations in pasture respond differently to different grazing pressures.
  • Heavy sheep grazing (block grazing) can eliminate Horehound seedlings.
  • Less intense grazing pressures can favour Horehound by allowing stock to graze desirable species and avoid the less palatable weed.

Biological control

  • Biological control is the use of a living species, usually an insect, mite or disease, to control a weed.
  • Biological control will not eradicate Horehound, but can be used in conjunction with other control methods.
  • Biological control agents that have been released in Tasmania include the Horehound plume moth.
  • For more information on biological control programs in Tasmania contact the Tasmanian Institute of Agriculture

Chemical control

Use herbicides in accordance with label. Refer to APVMA permit PER13160 where herbicide is to be used in non-cropping and bushland areas

Application method

1. Boom spraying

  • Stage of growth - Actively growing to mature
  • Location - Non-legume pasture
  • Suggested herbicide - Kamba 500, Kamba M

2. Spot spraying

  • Stage of growth - Actively growing to mature
  • Location - Non-cropping and bushland
  • Suggested herbicide - NB All require permit. Roundup®Biactive™, Weedmaster Duo®

Derwent Catchment Project

PO Box 22 Hamilton TAS 7140  |  Phone (03) 6286 3211  |