Ants are small red or black insects that you may find on your orchids from time to time. Ants can find orchids attractive because the flowers secrete a liquid that the ants find appealing. Ants may not be as destructive to the plant as the passengers they are carrying with them which can range from aphids to other scale insects which can damage the plants. Ants can also be found living in the orchid compost.
In order to remedy an ant infestation of your orchids you first should observe the level of infestation. If the infestation is not large you can usually just visually identify the insects and pick them off by hand and move them to another location outside.
You can also rinse your orchids in water which can get rid of anything living on them. Try spraying the orchids and the roots and see if you can get them to fal off. You can also try soaking the plant and the compost also for a while to try and suffocate any leftover bugs.
You can also use any general insecticide for orchids and should have success. Mixing neem oil or mineral oil with water and spraying the plant can also help keep insects off of your orchids without harming them.
