There are times when we must resort to using some insecticide in our gardens and landscapes. One particular example that comes to mind is an invasion of squash bugs. They multiply so fast and are so destructive that controlling them can be like fighting a tidal wave. Neem is my go-to product when I must fall back to a quicker and more direct solution.
Neem oil is an extract made from the bark or seeds of the Neem Tree (Azadirachta indica). Neem is native to the Indian sub-continent. The useful nature of Neem has been recognized in those cultures for hundreds, if not thousands of years as a natural anti-bacterial and anti-fungal agent and a natural insect repellant. The compound salannin found in Neem oil is more effective at repelling mosquitos than the commercial product Deet.
Use as an Insecticide
Neem oil is not a systemic insecticide when it is used as a foliar spray. It will not enter the system of your plants when sprayed. Using Neem as a foliar spray requires that the spray comes in contact with the insects to be effective. The compound in Neem that affects the insects is Azadirachtin. Azadirachtin prevents the insect from molting, inhibits feeding, and, on some insects, prevents the eggs from developing and hatching. When spraying, it is important to spray the underside of leaves and stem bases as well as the tops of the leaves.
When used as a soil drench, Neem tends to act as a long-lasting systemic insecticide, entering the plant’s system and spreading through the leaves where the insects consume it. It has the same methodology on attacking the insects as a foliar spray.
I mix my Neem oil solution as follows:
1.5 ounces of Neem Oil per gallon of water
2 tablespoons of liquid dish soap (insecticidal soap may be substituted)
2 tablespoons of citrus oil or orange oil (pure oil not mixed with any wax or detergent)
Mix thoroughly in your tank sprayer and spray using a tip setting that will deliver a heavy spray, not a mist.
Neem oil is effective against a wide range of destructive insects. It is most effective against insects that go through a complete metamorphosis during their life cycle. It is used against aphids, whiteflies, thrips, hornworms, mealybugs, leafminers, gypsy moths, weevils, webworms, loopers, psyllids, and sawflies. A USDA study has shown that Neem oil will repel cucumber beetles for up to 6 weeks.
Other uses of Neem oil include removing head lice and as a moisturizing agent in many cosmetics as well as an antibacterial and antifungal agent in some toothpaste.
Neem oil has been deemed harmless to humans, animals, and most beneficial insects. It will not harm earthworms, so it is suitable to use in your garden as a soil drench. Research shows that insect pests are unable to build up a genetic resistance to Neem oil over time.
As with any spray or when using pressure equipment, wear the appropriate safety equipment, including gloves and eye protection. Follow the manufacturer’s recommendations when using pressure equipment.
As with any insecticide, follow the label directions for use.
Neem is not a contact killer. It may take up to a week to notice any real result. Be patient
On stubborn pests, especially squash bugs, repeated applications may be necessary.
Starting an early application regimen is important. Don’t wait until you are overwhelmed with insects. If it looks like you are losing the battle with other methods, begin your Neem oil application quickly and regularly.
Use what you mix immediately. Neem oil does not store well after it is mixed.
Neem oil is an effective insect control agent that can be used safely. It is a naturally occurring product, processed from the seed and bark of the Neem tree. Neem should be a part of every organic gardener’s tool kit.
Links and Resources
For more information about organic gardening, lifestyles, and living, visit our website at West Texas Organic Gardening.
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