With both indoor and outdoor gardening comes pests. These insects can cause significant damage to your crop in a short amount of time. It is important to stay on top of these pests before they have a chance to cause any problems. This generally involves spraying pesticides on the crop in an attempt to kill them. Many of these pesticides are made from toxic chemicals, while others are made by synthesizing natural chemicals in a lab.

Neem oil, on the other hand, is special, it needs very little modification in order for it to be used as a highly effective pesticide for your plants. And it even has added benefits that these other pesticides don’t have!

What Is Neem Oil?

Neem oil comes from an Indian tree known by the scientific community as Azadirachta indica. The oil is extracted from the seed by crushing the seeds under extreme pressures to force out all of the oil contained inside.

The oil itself has a strong scent that falls somewhere between garlic and sulfur. It is actually quite potent in its natural raw form and comes to no surprise that most insects despise it.

How is it Used as a Pesticide

Neem oil is a natural pesticide by nature, and nothing needs to be done to it to make it kill or repel insects. As the name implies, however, neem oil is an oil, which means that it is not soluble in water. If you were to mix raw neem oil into a spray bottle of water and sprayed it, all the oil would be floating on the top of the water and would be the last thing sprayed onto the plants. This would probably clog the spray bottle and would deliver much too strong of a dose. Neem oil needs to be diluted in water for it to be safe for your plants.

The solution is called an emulsifier.

This is a class of chemicals which can be either natural or synthetic, that allow oils to mix into water. Soap is an emulsifier, which allows water to wash off the oils found on your skin and hair. Without it, the water would simply run over the oil without removing it.

In the case of neem oil, an emulsifier allows it to mix into the water in order to dilute it and makes it easy to spray onto the leaves of your plants. In most cases, this is the only addition needed to make a high-quality neem oil spray.

How Does Neem Oil Work?

Neem oil works in a similar way to horticultural oil (mineral oil) by smothering the insects and suffocating them. The oily nature of the spray coats the exoskeletons of the insect's body and seals it up to prevent air from entering or exiting the insect. Unlike mineral oil, however, neem oil has an added benefit through its unique chemical makeup.

Neem oil contains a chemical known as azadirachtin which has been found to prevent insects from feeding. If this persists for long enough the insect will die from starvation. Other actions of this chemical include a hormonal interaction which alters their natural hormone balance. These hormones are what regulate when an insect grows or develops into the next life stage (for example from nymph to mature adult), and regulates when an insect reproduces. By interacting with this system, azadirachtin can prevent an insect from breeding and developing or growing properly. Insects seem to know that neem is not good for them as well because even before an infestation, an application of neem has a strong repellent effect on insects.

Fortunately, neem is a long lasting pesticide as well, which makes it useful for preventative treatments as well as corrective. Some growers choose to spray their crops every few weeks with this safe and natural pesticide simply to repel any pests that happen to wander into their garden.

Is Neem Toxic?

Not only is neem oil non-toxic, it is actually good for humans. Neem oil can be purchased in health food stores as a topical oil for the skin and hair. It is used to treat head lice, eczema, dandruff, and as a natural insect repellant. It is safe to use on food crops and is one of the preferred methods of pest control by many professional vegetable growers for this reason.

It is slightly toxic towards fish, though, so avoid using this pesticide if you are running an aquaponics system.

Will Neem Hurt Plants?

Diluted neem oil sprays will not harm your plants, but if the oil is too concentrated, or used too often it can plug the stoma (breathing holes) on your plant's leaves and lead to damage. If the oil is allowed to accumulate, it can cause burn marks as it intensifies the heat of your lights or the sun. Best practices with neem oil suggest spraying only once every 24 hours, and avoid letting any spots accumulate the neem spray such as at the base of leaves.

Pick up your neem concentrate today to get started to keep your garden pest-free the natural way!