Description
Essential Oils for the Home & Garden
If you are trying to limit your exposure to toxic and synthetic chemicals in your garden and home essential oils can be valuable tools. They are well-known for their wellness virtues for humans, and can also be precious allies to protect your plants naturally and ecologically.
These oils have been used for thousands of years for their medicinal and cosmetic benefits, and their power lies in the hundreds of chemical constituents they contain. Whether you are trying to chase away garden pests from your vegetable or flower garden, protect your plants against diseases, or simply to improve their overall health, we can use these natural defences to our advantage in both our home and garden, using products you can store in your medicine chest. How cool is that!
Ravintsara Essential Oil
Ravintsara Essential Oil is steam-distilled from the leaves of the Cinnamomum camphora tree native to Madagascar. Known in the Malagasy language as “good leaf,” it has a fresh, clean, eucalyptus-like aroma and is highly regarded in aromatherapy for its calming and restorative properties.
In the Garden
Ravintsara essential oil acts as an effective broad-spectrum, bio-pesticide. Its active compounds, primarily camphor, linalool, and eucalyptol act as potent Contact Insecticides, Fumigants, and Repellents. Other minor components contribute strong Antifungal and Antibacterial defence mechanisms.
Research highlights its efficacy across several distinct categories. It’s biodegradable and leaves no toxic residue in soil or water.
Antifeedant & Repellent
The strong, distinct camphor-like aroma acts as a sensory deterrent, preventing insects from feeding on foliage or laying eggs on crops. Its high concentration of active biochemical compounds allows it to disrupt the nervous systems and biological functions of various agricultural, household and stored-product pests.
Eucalyptol comprises nearly half the oil, and this oxide provides powerful insecticidal, fumigant, and respiratory-disrupting properties. Sabinene enhances the oil’s penetration capability and works synergistically with other monoterpenes. α-Terpineol and Terpinen-4-ol are minor components that contribute strong antifungal and antibacterial defence mechanisms.
Agricultural & Garden Pests
The oil demonstrates strong insecticidal and repellent activity against Aphids like the Cotton Aphid, Whiteflies, and certain Caterpillar species by ingestion and contact.
Stored Grain & Pantry Pests:
Ravintsara essential oil is heavily researched for protecting stored grains from beetles like the Maize Weevil and Red Flour Beetle.
Maize Weevil (Sitophilus zeamais)
This is one of the most significant and economically devastating pests for stored grain crops in the country.
Red Flour Beetle (Tribolium castaneum)
This beetle is one of the most common pantry and stored-grain pests found throughout South Africa, thriving in warm, temperate and subtropical environments.
They are commonly found in pantries and cupboards, infesting flour, maize meal, oats, rice, and pet food. Commercially they are found in flour mills, bakeries, and agricultural storage facilities where grains are processed or stored.
Mosquito Larvae
The fumigant and repellent properties of the oil are shown to be highly effective against Mosquitos and their Larvae.
Miggies, Gnats, Midges
In South Africa muggies, midges, and gnats are names applied to a wide range of small flies and tiny biting midges. During warmer weather these little flying terrors are out in force. While most are harmless, some female biting midges inflict itchy welts and transmit livestock diseases.
They are highly prevalent near wetlands, dams, and standing water, particularly during warm spring and summer months.
They have four life stages, egg, larva, pupa and adult. With the exception of the gall midges, the larval stage in most midges is aquatic. This means that the eggs are laid in or near water or very moist areas, the larvae are found in the water or in mud near rivers, lakes or ponds, or even in very wet leaf mould in forests and other damp places. Some larvae will even inhabit wet animal dung.
Common Types in South Africa include:
Gall Midges (Cecidomyiidae)
The gall midges in the family Cecidomyiidae are important plant pests which can affect crops.
Non-Biting Midges (Chironomidae)
Often mistaken for mosquitoes these midges do not bite but form massive, annoying swarms near water and outdoor lights in the evenings.
Biting Midges (Culicoides)
These midges are also known as “no-see-ums” as they are extremely small (1–3mm). Females require a blood meal for their eggs, and in South Africa, they are significant vectors for diseases like African Horse Sickness, and spreading livestock diseases like Blue Tongue in cattle and sheep.
Black Flies (Simuliidae)
Black flies are often found near fast-flowing water, such as the Orange River. Females are day-biters and can be a severe nuisance to humans and livestock.
Control Methods
Eliminate Breeding Sites
Broad-scale spraying of natural lakes, dams, or rivers is typically ineffective and harmful to the ecosystem. However, you can treat smaller, stagnant water bodies on your property. Use environmentally friendly larvicides to stop midge larvae from maturing in shallow ponds or blocked gutters.
Remove or empty anything that can hold holding standing water in the garden or on the patio, like pot plant drip trays, pool covers, and bird baths.
Soapy Water:
You can kill larvae in standing water by spraying the surface with soapy water which breaks the surface tension and causes them to sink and drown.
Spraying Surfaces & Foliage
Adult midges rest on shaded vegetation, walls, patios and screens during the day. Applying a surface spray to external house walls, fences, vegetation, and insect screens will help to control them.
Using essential oils like ravintsara, eucalyptus, lavender, or cinnamon oil, or a combination of all four will also deter miggies and other pests. Adding the oils to a diffuser also works well indoors or in outdoor entertainment areas. However, because adult midges constantly migrate from nearby natural water bodies relying on spraying oils alone is a temporary fix.
Spraying Plant Foliage
Adult midges rest on shaded vegetation, walls, patios and screens during the day, so spray the lower, shaded foliage of dense bushes and trees in your garden where midges seek shelter from heat and wind.
Indoor Protection
Keep windows closed at night and, if possible, fit tightly woven insect screens.
Fumigant Action & Protection for Stored Products
Research shows that the essential oil of Ravintsara acts as an excellent deterrent for stored-product insects. Thanks to its high volatility, the vapour quickly penetrates enclosed spaces or plant structures like greenhouses, suffocating target pests.
The essential oil can be introduced to sealed storage containers to deter pests and affect adult development without impacting the germination rate of legumes or cereal.
For protection, add a few drops of pure essential oil to porous clay pucks or sachets and place them inside sealed storage containers. The released fumes safely repel beetles without diminishing seed viability or germination rates.
Impregnating storage bags with essential oil has been studied as a tool to manage and repel crop-destroying insects without using harmful chemical residues.
The Cotton Wool Method listed below is also effective.
Antifungal & Antimicrobial Activity
Ravintsara essential oil also acts as a bio-fungicide, preventing the germination of pathogenic spores on plant leaves.
Garden Spray
Mix 10-20 drops of the essential oil in 1 Litre of water with an emulsifier. Shake well, and regularly while spraying down the foliage of plants and surfaces.
In the Home
Clean, crisp, and clarifying, Ravintsara Essential Oil is steam distilled from the leaves of trees grown in Madagascar. It is thin and clear to pale yellow, with a fresh, medicinal aroma and subtle eucalyptus-like notes, this oil is a favuorite in immune-boosting and respiratory blends, especially during seasonal changes.
Highly regarded for its antiviral and decongestant properties, Ravintsara is a powerful ally for supporting wellness and promoting clear breathing. It also offers a calming effect, making it ideal for diffusing in times of stress or tension. Whether used in aromatherapy or topical blends, this essential oil is both gentle and effective.
When diffused indoors essential oils will deter many indoor pests.
- Add a few drops to a diffuser to create a peaceful, meditative atmosphere.
- Dilute with carrier oil for use in massages or skincare applications.
- Combine with Epsom salts and other relaxing oils for a deeply calming bath soak.
How to Use Essential Oils for Pest Control
When it comes to organic gardening, prevention is better than cure, and spraying crops regularly with essential oils to prevent insect infestation and disease is the most effective method. This will not only chase pests away, but also make your garden smell great!
Always use pure essential oils, and because they are so potent, always dilute them first.
How to dilute essential oils
One of the drawbacks of using essential oils in the garden is that the levels of terpenes and other constituents can vary greatly depending on the region where the plants are grown, genetics, climate and other seasonal factors. Therefore, maintaining consistency in the chemical profile of the oils is hard.
For example, Rosemary oil extracted from plants growing in two different regions of Italy will contain varying levels of α-pinene, ranging from 11% to 36%. Another study showed that essential oils extracted from different chemotypes of garden thyme did not have the same toxicity against the bean weevil.
This is the reason why, if you look for exact recipes for the oil you wish to use in the garden, you will find many different quantities of oil versus water used.
Another factor to take into account is the actual number of drops in a milliliter can vary greatly depending on the thickness of the liquid: Thicker liquids like essential oils produce larger drops, meaning it takes fewer drops to make 1mL. Different dropper bottles or droppers also have varying nozzle sizes, which changes the volume of a single drop.
In standard pharmaceutical measurements, 1 mL is equal to approximately 20 drops (meaning 1 drop is about 0.05 mL). Therefore, 10 drops are typically equal to about 0.5 mL.
This is why physicians do not rely on counting drops, as this can lead to incorrect dosing. Instead they use an oral syringe, a graduated measuring cup, or the specific dropper provided with the medicine.
CAUTION:
Because the actual number of drops in a millilitre can vary greatly depending on the thickness of the liquid and varying nozzle sizes, which changes the volume of a single drop, I recommend starting with the lowest recommended dosage. You can always increase it later.
Preventative Spraying
A general guideline when mixing sprays to deter insects, and for anti-fungus protection is to mix 4–8 drops of Essential Oil in 1 Litre of water with an emulsifier.
Garden Sprays
At certain times of the year various pests and diseases will be more prevalent, so for stronger protection dosages can be increased.
Generally you will find recommended dosages are between 10-20 drops per Litre of water.
Always Test Sprays First
Unless you apply very high doses of essential oils, they are perfectly safe to use in the garden. However, because the strengths of essential oils vary, to ensure they do not cause leaf burn, it’s important to always test your spray on a small, isolated area of the plant first. Wait at least 24 hours to check for damage before applying it everywhere.
A good method of remembering which leaves you tested your spray on is to tie string or ribbon onto the stems that have been sprayed.
Take Notes
Taking note of which plants were tested and the dosages used, will soon give you a good indication of the strengths your plants need for protection.
Mixing your spray
The Emulsifier:
Soap is essential as an emulsifier as essential oils do not mix with water and will float to the top, potentially burning your plants. A gentle liquid dish soap, pure liquid Castile or Black soap can be used.
Approximately one teaspoon of liquid soap emulsifier is used in one litre of water. Witch hazel, Vodka, or apple cider vinegar also emulsifies oil and water.
The Method:
In a small glass container, mix your essential oils with your emulsifier, then add some of the water and stir well. Warming the water helps with emulsification. Add the oil mix to the spray bottle with the rest of the warm water. Agitate well and also regularly whilst spraying.
Applying your Oils
Spraying in the middle of a hot, sunny day can cause leaf burn, so always apply the mixture in the cool of early morning or late afternoon. Remember to agitate the spray bottle well before use, and regularly while spraying. Ensure that you spray underneath the leaves where insects commonly hide.
During the cooler times of the day beneficial daytime pollinators are not that active. Never spray plants if you can see beneficial pollinators like bees around the plants. Even organic sprays can be abused in the garden, so as they say “everything in moderation”.
NOTE: The strength of the oils will evaporate, so reapply to plants after rain, every 2 weeks, or as needed.
Cotton Ball Method
To target specific insects in large numbers, like ant hills or rodent burrows, take some cotton balls and add a few drops of essential oils to them. Place the cotton ball right onto the ant hill, burrow or other insect grouping. This will cause them to relocate immediately. If that doesn’t work immediately you should repeat the process using a stronger solution.
You can also rub the oils onto any hard surfaces to create a long-lasting barrier.
Hanging Strips to Deter Pests
Add essential oils to a bowl of warm water and soak strips of pretty material or ribbon in the water before hanging onto the branches of fruit trees, or near edible gardens and ornamental shrubs.
Is there a waiting period before harvesting?
You should not eat vegetables and fruits immediately after spraying them with essential oils. These oils are highly concentrated and consuming them without a waiting period or proper cleaning can cause digestive upset, inflammation, or irritation of the mouth and oesophagus.
Essential oils degrade in sunlight and waiting 24 hours should be sufficient. Ensure that you always wash your food well and all will be fine.
Storing Essential Oil Mixes
Try to mix up only sufficient spray to use in a day, or within 24 hours of mixing. Once exposed to water and oxygen, oil-based garden sprays begin to separate, degrade, and lose their effectiveness.
If you do have any left-over, store it in a glass bottle in a cool, dark place, not in your plastic spray bottle, as essential oils break down quicker in plastic. Agitate well before using again.
