Neem oil is a powerful organic solution for managing garden pests and indoor plants. It is of plant origin (extracted from neem tree seeds & leaves) and is native to tropical regions. Aside from neem oil as organic pest control, organic neem oil use was also significant to cure diseases in humans and plants for centuries in old ages.
In addition to its benefits as organic pesticide spray in plants, neem oil is also used in the cosmetic industry. The products that contain neem extracts are pet shampoos, toothpaste, and soaps.
What is Neem Oil?
Neem oil is an organic extract of neem plant leaves and seeds. It is yellow to brown with a bitter taste and garlic-like smell. Neem oil is a mixture of many compounds, and the most active ingredient of this oil is azadirachtin which works as a natural pesticide for organic use.
Organic gardeners love to use neem oil products due to their excellent benefits to their plants and zero residual in the environment. They use neem oil on vegetables and houseplants as an insecticide, fungicide, and miticide.
According to the environmental protection agency, neem oil insecticide is safe in indoor environments because it does not harm pets and humans.
Related: How To Use Neem Oil On Houseplants? A Comprehensive Guide
How Does Neem Oil Work?
Neem oil mixture contains azadirachtin, which interferes with the insect reproduction cycle. These neem oil pesticides retards insect growth and development and manage their populations in indoor plants.
Once the insect ingests the plant leaves sprayed with neem oil concentrate, they forget to eat, molt, mating, and egg-laying. The neem oil spray functions as an antifeedant and kills pests. Furthermore, neem oil spray has a strong smell that distracts the insects and protects plants from pest damage. Also, it does not harm the beneficial insects.
Uses of Neem Oil as Organic Pest Control
Neem oil is effective against a wide variety of houseplant insects. It works as both insecticide and repellent. Neem oil can control almost 170 species of garden and houseplant insects. The neem seed oil spray manages the infestations of spider mites, aphids, whiteflies, mealybugs, russet mites, scale insects, root aphids, winter moths, and springtails.
Neem oil spray is also effective against nematodes and fungal infections. In addition, its spray can prevent houseplant from root rot, powdery mildew, and foliage discolorations.
Neem oil functions as an antifeedant, smothering, and insect growth disruptor to manage pest populations.
Use Neem Oil to Kill Whiteflies
Whiteflies are the most common bugs of houseplants that suck their juices and cause discoloration of leaves. Unfortunately, these tiny piercing-sucking pests are also the worst enemies of garden plants and vegetables. So, to get rid of them, neem oil mixture can be used because of its natural pesticide properties.
Applying neem oil on houseplants will stop the feeding and reproduction of larvae and adult whiteflies. Therefore, there will be no whitefly population explosion when there is no reproduction.
Use Neem Oil to Destroy Spider Mites
Spider mites are also the most common pest of indoor plants. As compared to other houseplant pests, it is difficult to control because they are so tiny and invisible to make an eye. And the presence of spider mites only appears when the plant shows signs and symptoms of damage. However, the neem oil applications prevent their infestations and damage.
Spray houseplants with 70 percent pure neem oil in dilution form. Neem oil kills the spider mites by interrupting their physiology and life cycle.
Use Neem Oil to Kill Thrips
Thrips are active and sucking plant pests that feed in large groups and reproduce quickly when in favorable indoor conditions. They turn the host plant leaves into pale yellow and brown. So, it is best to detect the thrips and control them early.
Systemic treatment of plants with neem oil spray is best to repel the thrips to manage thrips on houseplants.
First, apply neem oil dilution during watering; it is then absorbed by plant roots and moves up to leaves. When thrips feed or suck plant sap, they will soon be killed by absorbed neem oil insecticide.
Note: The benefit of the systemic treatment of houseplants with neem oil insecticide will protect them from common bugs throughout their lives.
Use Neem Oil to Manage Mealybugs
Just like aphids and whiteflies, mealybugs are sap-sucking insects that can easily be spotted through their large, cottony, and oval-shaped bodies. They tend to establish feeding sites and actively suck out plant juices from the phloem. Their damage includes loss of plant vigor, falling leaves, and wilting.
Diy neem oil spray can effectively manage adult mealybugs and their fast-feeding crawlers. To get rid of this houseplant pest, simply dip a cotton swab in pure neem oil and rub it onto the buds and stems where mealybugs are present. Neem oil will kill the mealybugs through contact.
In the case of larger mealybug populations that are also difficult to control, make a neem oil dilution with water and apply it on plants regularly to combat them. Apart from this, neem oil insecticide can be used as a systemic treatment to discourage young crawlers.
Use Neem Oil as Soil Drench to Kill Fungus Gnats
Fungus gnats—these tiny mosquito-like bugs lay eggs in damp and nutrient-rich soil. The young fungus gnat larvae also damage indoor and outdoor plant roots. So, their management is most important because larvae feed off the roots, and adults damage the leaves and flowers.
Use neem oil insecticide as a soil drench and foliar spray to control fungus gnat larvae and adults on houseplants.
Mix the neem oil insecticide with water, add to the soil, and absorb. Once neem oil dilution is wholly absorbed in the soil, it will repel females to lay eggs and kill the larvae. At the same time, the foliar spray will repel the adult fungus gnats.
Use Neem Oil as a Leaf Shiner
Aside from neem oil’s insecticidal properties (natural pest control), it can also be used as a leaf shiner. Plant leaves with a diluted neem oil solution for this spray and then rub leaves with a soft fabric. It will bring the desired leaf shine and repel the common houseplant bugs.
Note: The pros of using neem oil as a leaf shiner is it will not block the photosynthetic activity of leaves, unlike other products—coconut oil and banana skin.
Use Neem Oil to Kill Aphids
Aphids are rapidly reproducing insects among other houseplant bugs. They are also responsible for severe damage to their host plants. Other chemical pesticides such as horticultural oils, essential oils, neem oil uses are also best.
To achieve zero population of aphids, mix the neem seed extract with insecticidal soap and water. And then, apply this mixture to infested plants; make sure to thoroughly use it on both the upper and lower sides of leaves. This mixture is effective in controlling aphids populations on indoor and outdoor plants.
How to Use Neem Oil on Houseplants?
The materials and equipment we need to make neem oil spray are:
- Spray bottle
- Diy neem oil spray or ready to use neem oil
- Water
- Mild detergent or soap
Mix one to two tablespoons of insecticidal soap or dishwasher in one gallon of water. The soap detergent will act as an emulsifier for mixing neem oil in water. Next, add two tablespoons of ready-to-use neem oil or your DIY oil to the mixture. Apply this mixture on leaves (underneath and upper side of leaves) until the plant is entirely wet and dripping.
Reapply this mixture the next day and repeat the application process for a period of seven to fourteen days. Once the insect problem is gone, apply it biweekly as a preventive measure.
Note: The soap detergent in the neem oil mixture will work as an emulsifying agent and kill the aphids and whiteflies. In other words, it enhances the effectiveness of neem oil.
Tips to Achieve the Best Results of Spraying Neem Oil on Houseplants
Following tips while using neem oil as organic pest control provide the best result:
- Neem oil foliar spray should fully cover the insect body to interfere with their life cycle and kills them
- The houseplant bugs that reproduce rapidly and simultaneously have all life cycle stages should regularly be followed with neem oil applications. Applying neem oil at the early growth stages of the pest life cycle is also best and wiser, such as egg and larvae.
- Because it is an oil, do not use or spray neem oil on plants sensitive to sunlight or burn. Also, do not apply it on foliage during hot weather with direct sunlight on plants.
- Neem oil has a strong smell that may cause allergies to pets or harm beneficial insects. Therefore, always take indoor plants outdoors then spray them with neem oil insecticide to avoid this. In this way, the smell will only remain until the solution dries out.
- Always apply neem oil spray in the morning or the evening when the beneficial insects are not feeding or pollinating.
- Always keep an eye on the day’s temperature to avoid foliage burn.
Benefits of Using Neem Oil Spray
Neem oil is a natural pesticide from neem trees and seeds for insect control and pest management. Following are the excellent benefits of using neem oil as an insecticide and pesticide.
- In contrast to other seasonal pesticides used at certain times, neem oil can be used throughout the planting season.
- Neem oil is effective at any time of the planting season because it harms all stages of the insect life cycle (egg, larvae or crawlers, pupae, and adult)
- Neem oil controls Japanese beetles, moth larvae, and mites—functions as a miticide.
- Hydrophobic neem oil spray controls pests and fungal diseases such as rust, blight, powdery mildew, leaf spot, scab, anthracnose, and black spot.
- Neem oil does not harm beneficial insects such as bees, ladybird beetles, butterflies, and birds.
- It does not harm beneficial soil organisms such as earthworms.
Frequently Asked Questions
Is Neem Oil Safe For Organic Gardening?
Yes, neem oil is entirely safe for organic gardening and indoor spaces. Because it is of plant origin and commercially available as a natural pesticide, compared to other pesticides, it can kill hundreds of insect pests and be applied throughout the planting season. Neem oil insecticide is also effective against nematodes, fungal diseases, and mites (not russet and spider mites).
Do I Need to Dilute Neem Oil?
Yes, it is essential to properly dilute and emulsify neem oil in water and spray it on indoor plants. Because it will not burn the plant leaves and work best to control insects, if it is not appropriately diluted in water, it will appear globby and unevenly cover plant surfaces.
What is The Ratio of Neem Oil to Water?
Neem oil is mixed with water as:
- Two tablespoons of neem oil with one liter of water for 70 percent pure neem oil
- 0.5 tablespoon of neem oil per quart of water
How Long Does it Take for Neem Oil to Work on Plants?
Neem oil works as an antifeedant, smothering, and insect hormone disruptor agent. However, applying neem oil spray on houseplants does not work right away. It takes three to four days to get the desired results by neem oil treatment.
What Happens if You Use Too Much Neem Oil on Plants?
Too many neem oil applications will harm the plant. It will burn the plants and cover the leaf surface hard. Because of that, plants will not photosynthesize completely and prepare their food. Therefore, too many applications of neem are not recommended for gardens and houseplants.
However, this problem can be fixed by diluting neem oil in water plus insecticidal soap.
What Garden Pests Does Neem Oil Kill?
It is a natural, broad-spectrum, and safest pesticide that kills various garden pests. Not only garden pests, but this product can also eliminate fungal diseases. It damages mites, scabs, powdery, anthracnose fungal pathogens, etc.
Can You Mix Neem Oil and Pyrethrin?
Yes, it is possible to mix neem oil and pyrethrin only to enhance the efficacy of both chemicals. Because neem oil is a mixture of many compounds that actively work on various pests, enhanced effectiveness can be achieved against problems by mixing these chemicals.
What Are the Side Effects of Neem Oil?
There are no side effects of neem oil as a spray in plants. However, it has a strong smell that may irritate pets and humans. So the best way to avoid this garlic-like strong smell is to spray plants outdoors. Then, take these plants indoors when the neem oil spray goes away.
Sources for Further Reading
- D. (2021, August 13). How to Properly Emulsify Neem Oil & Make a Safe Garden Pest Spray. Homestead and Chill. Retrieved February 21, 2022, from https://homesteadandchill.com/emulsify-neem-oil-spray/
- Woodstream, W. (2020, November 5). 24 Amazing Benefits and Uses of Neem Oil for Plants. Safer Brand. Retrieved February 21, 2022, from https://www.saferbrand.com/articles/benefits-uses-neem-oil-for-plants
- M. (2021, September 23). How to Use Neem Oil to Protect Plants From Pests. MasterClass. Retrieved February 21, 2022, from https://www.masterclass.com/articles/neem-oil-for-plants
After learning how to use neem oil as organic pest control, make sure to read our other plant care tips:
What is Silty Soil & How to Improve the Silt?
Importance of Soil pH and Nutrient Availability for Plant Health
What are the Effective Ways to Fix Nitrogen Toxicity in Houseplants?