- Neem Insect Spray: Making and Using Neem Garden Spray
- Neem Oil Amounts For Insect Spray
- Method For Preparing Neem Spray
- Additional Instructions
- Control Pests and Diseases Safely With Neem
- Control these pests with neem
- Do You Mean Business When Tackling Garden Bugs? Then Neem Them!
- Neem oil poisoning: Case report of an adult with toxic encephalopathy
Neem Insect Spray: Making and Using Neem Garden Spray
When making your own neem insect spray you can adjust the concentration to the purpose and situation.
There are no hard and fast rules, only guidelines.
Some insects are more persistent than others. For those you may want a stronger solution.
Regular spraying for prevention is different than fighting a severe infestation. A preventive spray can be more diluted.
For a neem garden spray 0.5% to 1% is a good general purpose solution. Depending on the purpose you may want to increase that to up to 2%.
Use your own observations and common sense. Keep in mind that neem oil insecticide does not kill insects instantly . Wait for at least a week to judge the effects.
Neem Oil Amounts For Insect Spray
For 1 liter or 1 quart of a 0.5 % dilution of neem plant spray you need:
- 5 ml (1 tsp) neem oil (use pure, cold pressed oil)
- 1-2 ml (1/3 tsp) insecticidal soap or other detergent
- 1 liter (1 quart) warm water
Just multiply these amounts if you want to make a bigger batch.
If you want to make a more concentrated batch multiply both the amount of neem oil and the amount of soap used.
For 20 liters of a 1% solution of neem garden spray you need:
- 200 ml neem oil
- 30 ml insecticidal soap
- 20 liters of water
Alternatively, for US readers…
For 4 gallons of a 1% solution of neem spray you need:
- 6.5 oz neem oil
- 5 tsps insecticidal soap
- 4 gallons of water
If you have trouble dissolving the oil, use more detergent.
Method For Preparing Neem Spray
- Use a high quality, organic, cold pressed oil.
- Use warm water if possible. If making a large batch, first make a premix in a small amount of warm water, then add that to the rest of the water into the big container.
- Mix the warm water with the soap first!
- Then slowly add the oil while stirring vigorously.
- Fill the mix into your sprayer.
- (Or fill the premix into your sprayer, which should already contain the rest of the water. Mix well.)
- Keep shaking or otherwise agitating the mix while spraying.
- Use the mixture within eight hours.
Spray the neem insecticide solution on all the leaves, especially the undersides where insects to hide. If you have plenty drench the soil around the roots as well. It does not hurt, neem oil is actually good for your soil.
Use your neem insect spray as quickly as possible, definitely within eight hours. Once mixed with water the neem oil starts breaking down. Always make a fresh batch for spraying, and only prepare the amount you need.
How often should you use neem garden spray? The suggestions below are general guidelines. Keep a close eye on things and fine tune as needed. If you are worried about sensitive plants, spray just a little bit in a small area, wait for a day or two, and see what happens. If you use insecticidal soap you should not have any problems.
Neem plant spray as a preventative measure: Spray once a fortnight using a 0.5 % solution. This should prevent any insect problems in the first place.
Neem insect spray to fight an infestation: When spraying the first time, throroughly drench all leaves and the soil around the plant. Then spray once a week until the problem disappears. If it rains you may need to respray sooner. If you are dealing with a less sensitive insect species you may need to increase the concentration of the neem spray. See how you go.
Learn more about making, using and buying neem insect spray.
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Control Pests and Diseases Safely With Neem
Neem comes in spray bottles and in concentrated form and can be used safely on both ornamental and edible plants.
These days, savvy gardeners are reaching for a gentle but effective product to deal with many pest and disease problems: neem. Extracts from the neem tree (Azadirachta indica), which is native to India, have been used for centuries for everything from cleaning teeth to killing aphids.
The leaves are used in analgesic teas and skin-soothing tinctures, and powder made from the leaves has long been used in folk remedies for cuts and abrasions, because it is an effective antibacterial agent.
The bark is incorporated into body care products, the twigs are used dental floss, and various neem extracts are often included in toothpastes because they help fight cavity-causing bacteria. Neem seed oil has antibacterial properties, and crushed seed is considered a valuable soil amendment.
Gardeners can also use neem oil to control or prevent many common plant pests and diseases (see the list below). It biodegrades quickly and, in small doses, is nontoxic to mammals, so it’s a good choice for using around the house. Neem product manufacturers list dozens of insects that can be effectively controlled with neem.
It is effective against some of the more common caterpillar pests, and Japanese beetles, June beetles, and scarab beetles will not feed on neem-treated plants. Neem will also control the larvae of a number of lawn pests usually lumped together as “white grubs.
” Sprays will also help to control disfiguring foliar diseases mildews and black spot.
Control these pests with neem
Neem can be used to combat a number of pests, including the common ones in the list below.
The active ingredient in neem, azadirachtin, consists of compounds called liminoids, which act somewhat steroids. When insects eat neem-coated foliage, the liminoids disrupt normal hormone production and processing, causing a loss of appetite in some insects and interfering with normal reproduction, maturation, and molting patterns in others.
Applied as a spray, neem will smother certain pests on contact and will also prevent eggs from hatching. Neem oil is available both in concentrate (to be mixed with water) and in ready-to-use handheld spray bottles.
It is safe to use on both ornamental and edible crops and can be sprayed on herbs and vegetables up to the day of harvest.
Applying neem oil to a drought-stressed plant can burn the foliage, so water plants thoroughly before using it.
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Do You Mean Business When Tackling Garden Bugs? Then Neem Them!
Neem oil insecticide is often a great solution if you are having problems with insects, mites, or fungi bothering your plants.
What organic gardeners love about it is that it is safe to use: It will not harm you, your kids, your pets, or your livestock.
It is safe even for most wildlife, its insecticidal properties being targeted to specific pests that damage garden plants. Learn examples of pests that neem is effective against.
Neem oil is pressed the seeds obtained from neem trees. The botanical name for this tree is Azadirachta indica. The tree is a broadleaf evergreen that is indigenous to India and adjacent areas. The tree belongs to the mahogany family and commonly becomes 50 to 60 feet tall.
In addition to its use as an organic insecticide spray, this oil has been used medicinally and in the cosmetics industry. Neem oil and the tree from which it is derived are so called from the Sanskrit, nimba.
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One seller of the product, Dyna-Gro, explains how it works as an organic insecticide: “It disrupts insects' hormonal balance so they die before they molt to the next life stage.”
The National Pesticide Information Center states, “Neem oil is made of many components. Azadirachtin is the most active. It reduces insect feeding and acts as a repellent. It also interferes with insect hormone systems, making it harder for insects to grow and lay eggs.”
According to the EPA, “Azadirachtin acts in the following ways: It deters certain insects, such as locusts, from feeding and it interferes with the normal life cycle of insects, including feeding, molting, mating, and egg-laying.” Just how much Azadirachtin a product you buy off the shelf contains is not, however, always readily apparent; the label may refer to “other ingredients,” then fail to specify.
The Monterey Bay Spice Company sells a “70% Neem Oil” product. The OMRI on the container stands for “Organic Materials Review Institute.” In the organic gardening community, an OMRI listing lends a product credibility. Monterey Bay supplies the following instructions for application:
- Mix the neem oil at the rate of 2 tablespoons (1 ounce) per gallon of water. Mix the solution thoroughly.
- Spray all plant surfaces (including undersides of leaves) until completely wet.
A great sprayer to use to apply neem oil on plants is Garden Gorilla. This company puts out one of the easiest garden sprayers to use.
When applied as a preventative, neem oil should be applied on a 7- to 14-day schedule according to the manufacturers of 70% neem Oil. To control a pest or disease already present, they recommend an application on a 7-day schedule.
Neem oil insecticide kills some pests after they have eaten leaves sprayed with it, while it repels others with its strong smell. Neem oil is used to control many pests, including whitefly, aphids, Japanese beetles, moth larvae, scale, and spider mites.
As it kills mites, which are not insects but, instead, related to spiders and ticks, it is listed as a “miticide.
” Sprays containing clarified hydrophobic extract of neem oil are also used as fungicides against rust, black spot, mildew, leaf spot, scab, anthracnose, blight, and botrytis.
Cappi Thompson / Moment / Getty Images
Besides being an organic insecticide, using this product allows you to target pests specifically as opposed to beneficial insects such as bees and lady beetles. By definition, “pests” are the insects eating your plants, and neem oil, when properly applied, kills an insect only if it ingests the sprayed foliage (bees and lady beetles do not eat plant leaves).
Neem oil poisoning: Case report of an adult with toxic encephalopathy
From: Department of Medicine, Pramukhswami Medical College, Karamsad, India
Find articles by Ajay Mishra
From: Department of Medicine, Pramukhswami Medical College, Karamsad, India
Find articles by Nikhil DaveAuthor information Copyright and License information DisclaimerCopyright : © Indian Journal of Critical Care Medicine
This is an open-access article distributed under the terms of the Creative Commons Attribution-Noncommercial-Share A 3.0 Unported, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Neem oil has widespread use in Indian subcontinent due to its many bioactive properties. Azadirachtin, an active ingredient, is implicated in causing the effects seen in neem oil poisoning. Neem oil poisoning is rare in adults.
This report highlights the toxicity associated with neem oil poisoning in an elderly male. The patient presented with vomiting, seizures, metabolic acidosis, and toxic encephalopathy.
The patient recovered completely with symptomatic treatment.
Keywords: Neem oil, poisoning, toxic encephalopathy
Neem oil is a vegetable oil obtained from the seed kernels of Neem tree (Azadirachta indica), an evergreen of the tropics and sub-tropics. It is deep yellow in color and has garlic– odor. It contains active ingredients azadirachtin, nimbin, picrin, and sialin.
Azadirachtin, a complex tetranortriterpenoid, is implicated in causing the effects seen in neem oil poisoning. In children, neem oil is reported to cause toxic encephalopathy and Reye's– syndrome.
 We report a case of neem oil poisoning in a 73-year-old male who presented with vomiting, seizures, metabolic acidosis, and toxic encephalopathy.
A 73-year-old man with the medical history of diabetes mellitus type 2 and psoriasis presented to the emergency department with complaints of vomiting and drowsiness, 1 hour after accidental ingestion of 20 ml of Neem oil. The patient's current medication included human Mixtard insulin (30/70), 16 U before breakfast and 10 U before dinner.
At presentation, the patient was drowsy with Glasgow coma scale of 13/15. His pulse rate was 110/min, respiratory rate 28/min, oxygen saturation of 95% at room air, and blood pressure 150/90.
Physical examination was unremarkable. Systemic examination showed: bilateral equal and reacting pupils with no meningeal signs and no focal neurological deficits.
Respiratory, Cardiovascular and abdominal examination were unremarkable.
In the emergency department, the patient developed generalized convulsions with loss of consciousness. He was intubated and managed initially with intravenous lorazepam. In the intensive care unit, he was managed with insulin and symptomatic treatment.
Investigations at presentation showed: Hemoglobin 13.3 gm/dl, leukocyte leukocyte count 16800/μl, red blood cell count 4.41 million/cmm, platelet count 375000/μl, blood sugar 298 mg/dl, serum osmolality 277 mosmol/kg, and normal serum lactate level.
An arterial blood gas analysis showed metabolic acidosis: pH 7.34, pO2 81, pCO2 24, HCO3 16, and pO2/FiO2 385. He had normal urine analysis, serum electrolytes, liver, renal, and thyroid function. MRI scans of brain showed chronic ischemic changes due to small vessel disease.
ECG and radiograph of the chest were normal.
Investigations repeated on day 2, 3, and on discharge showed: Normal electrolytes, arterial blood gas, liver, and renal function. During the course of illness, he remained drowsy for 4 days and recovered without any complications. He was discharged after 1 week.
Neem oil, as a traditional medical remedy, is used as anti-bacterial, anti-fungal, insect repellent, and treatment of skin diseases. Traditional routes of administration of Neem extracts included oral, vaginal, and topical use.
Neem oil comprises mainly triglycerides, steroids (campesterol, beta-sitosterol, stigmasterol) and many triterpenoids, of which azadirachtin is the most well-known and studied.
The azadirachtin content of neem oil varies from 300 ppm to over 2500 ppm, depending on the extraction technology and quality of the neem seeds crushed.
In children, there are several case reports of Neem oil poisoning causing vomiting, hepatic toxicity, metabolic acidosis, and encephalopathy.[2,3,4] Lai et al., reported 22 cases of neem oil poisoning in infants, who were given single doses of Neem oil (few drops to 5 ml), presented with features of toxic encephalopathy, metabolic acidosis, and hepatic toxicity.
The infants recovered completely with supportive treatment. Sundaravalli et al., in a case series of 12 children with neem oil poisoning, who were given single dose of Neem oil (25-60 ml), reported fatality in 10 cases with features of toxic encephalopathy and metabolic acidosis. Sinnaih et al.
, reported Reyes– syndrome in fatal cases of Neem oil poisoning in a case series of 13 children.
In adults, there are few case reports of Neem poisoning. Iyyaduria et al., reported a case of a 35-year-old female with suicidal poisoning, who presented after ingestion of 250 ml of Neem pesticide with encephalopathy and metabolic acidosis with no evidence of hepatic and renal complications. She recovered completely with supportive management.
 Bhasker et al., reported a 35-year-female with Neem oil poisoning who presented with bilateral visual loss. Cranial MR imaging, showed symmetrical altered signal intensity bilaterally in the putamen region with extension to the posterior limb of the internal capsule.
Laboratory findings were within normal limits, and she recovered completely with supportive management.
There is no specific antidote available, and gastric lavage is not recommended for Neem oil poisoning. The management is primarily symptomatic. Our report highlights toxicity related to neem oil poisoning in an elderly male patient presenting with vomiting, seizures, metabolic acidosis, and encephalopathy.
He had no laboratory evidence of hepatic and renal complications. His symptoms resolved in 4 days with symptomatic treatment, and he was discharged after 1 week.
Azadirachtin (C35H44O16) manifests its toxicity possibly by interfering with mitochondrial bioenergetics, resulting in inhibition of the generation of the electrochemical proton gradient (primary form of energy generated in mitochondria).
Acute poisoning with inhibitors of electron transporting complexes causes symptoms such as muscle weakness, easy fatigability, hypotension, headache, facial flushing, nausea, confusion, and aggravation of latent myocardial angina.
The inability to utilize oxygen is manifested as a cytotoxic hypoxia wherein the chemicals cause a metabolic acidosis and hyperpnea, despite normal pO2.
However, inhibitors of the supply of reducing substrates for the respiratory chain cause a similar metabolic syndrome that is difficult to distinguish from inhibitors of the electron transport chain.
This case highlights the toxicity associated with Neem oil poisoning in an adult. Treatment is primarily symptomatic and recovery is usually complete.
Source of Support: Nil
Conflict of Interest: None declared.
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