Citrus Tree Oils

• Two well-known types of tree oils that are effective in killing roaches are mandarin oil and lime oil. Both of these oils lie under the category of citrus oils. Varieties of citrus oils are obtained from the outer covering of the citrus fruits and from the cuticle region of the citrus peels. Sometimes, tree oil can also be obtained from the leaves and flowers. These tree oils are safe to use at home or outdoors, as they do not cause any harm to pets or plants.
  
  The main function of the citrus oil is to kill insects. Lime oil is acidic and attacks the outer coating of roaches, which is made up of wax. Thus, when the roach comes in contact with the citrus oil, its outer wax coating is completely destroyed and the citrus oils seeps into the roach's internal system affecting its organs. The acidic content of the citrus oil partially dries and burns the organ lining causing the death of the roach and in return protecting the home from them.
  
  

Neem Tree Oil

• Neem oil kills roaches only if the oil is mixed into the bait and does not work as a contact poison. This oil is mildly toxic and when used in roach bait, it will kill the insect. Neem seeds contain azadirachtin, which is a common ingredient found in many pesticides. Moreover, the oil can also be sprayed on surfaces to repel roaches and discourage them from entering the territory, but spraying will not kill them. Adult roaches might not die after consuming the bait but may lose the ability to lay eggs in the future.
  
  

Eucalyptus Tree oil

• This essential oil has a strong odor that contains citral, which has insect repellent properties. Add a few drops of this oil to a bucket of water. Use this solution to mop the floors and wipe cabinets, cupboards and counters that are prone to roaches.
  
  

Tea Tree Oil

• This oil comes from a tropical tree that is well known for its strong antiseptic properties. This oil works as a deterrent for roaches and other household pests. The oil contains a strong medicinal smell and when ingested can be toxic. Dip cotton balls into the oil and leave them in places where roaches could enter the house to prevent them from crossing the barrier. In addition to this, a solution containing water with few drops of tea tree oil added can be used to wipe over cupboards and other surfaces to deter the entry of roaches.
  
  

Lemon Tea Tree Oil

• Lemon tea tree oil kills roaches by blocking their neural networks. These neural networks do not exist in mammal bodies and thus lemon tea tree oil can only cause harm to insects. They contain citral, which is poisonous to the roaches and can kill them by mixing it into the bait or through contact.
  
  

Considerations

• Not all varieties of tree oils are suitable for killing insects and roaches. Each type of oil contains its own chemical structure and has its own capabilities of targeting the roaches. The presence and structure of various aromatic compounds within the tree oil determine the oil's mode of action.