There’s no denying the draw of an orchid. The orchid has long been associated with sexuality (thanks to the Greek physician Dioscorides).
But more importantly, it can be a symbol of love, friendship, marriage, fertility, innocence, royalty, and more, depending on the color.
More interestingly, many of the 27,800 (and counting) varieties were eaten as an aphrodisiac.
But there’s one thing that makes this plant far less romantic when you give one to your partner – a pest infestation.
You don’t want to use harsh chemicals on this wonderful flower, but thankfully the gardener’s greatest natural ally, Neem oil, is a safe and effective pesticide when protecting these floral treasures.
How to Use Neem Oil for Orchid Pests
Using neem on an orchid isn’t much different than on other plants.
However, the orchid like the Phalaenopsis (moth orchid) can be a little more sensitive, so a few extra steps can be vital to a healthy plant.
Precautions with Neem Oil on Orchids
As mentioned, orchids can be a little more sensitive than some of your other ornamental plants.
The following considerations will not only keep your orchids happy and healthy but can be applied to other flowering plants as well.
- Avoid direct sunlight during treatment – Neem oil dissipates quickly, but a foliar spray is still water-based and can lead to sunburn when the wet leaves are exposed to direct sunlight.
- Don’t treat in temperatures above 85° degrees Fahrenheit – Neem oil loses potency at higher temperatures, and the heat may also lead to burns due to the oil content.
- Always test before treatment – Some orchid species can be more sensitive to neem oil. At the same time, individual plants can develop sensitivity, so test a small portion 24 hours before any treatment.
- Avoid the blooms – The flowers of many orchid species, including Miltonia and Masdevallia, can be sensitive to neem, even if the rest of the plant isn’t, so try not to get any on the flowers when using a foliar spray.
- Always spray outdoor plants at dusk or dawn – Bees and other beneficial insects are least active at this time, giving neem oil the 45 minutes to one hour needed to dissipate safely.
- Avoid using neem oil close to inhabited water features, as Azadirachtin is mildly toxic to many aquatic life forms.
Choosing the Type of Neem
There are three main types of neem, each with its own application and abilities.
100% percent cold-pressed raw neem oil is the unmodified form of neem oil.
Always make sure you buy cold-pressed, so it’s at the most potent and store in a cool, dry place.
Raw neem contains Azadirachtin, a natural insecticide that mimics the hormones of many insect species.
Used in soil soaks, the Azadirachtin becomes a systemic insecticide consumed by any pest that pierces or chews the plant.
Once ingested, Azadirachtin can block the appetite signals, cause infertility, and prevent nymphs from reaching adulthood.
Never use raw neem in foliar sprays due to the risk of chemical burns.
Neem cakes are the solids left over from creating raw neem.
These cakes have trace amounts of neem oil and Azadirachtin and commonly used as a supplemental fertilizer.
The exact NPK varies by manufacturer but is usually around 4-1-2.
Neem cakes won’t affect leaf-based pests but can be an effective barrier against grubs and other ground-based pests without harming earthworms.
Clarified hydrophobic neem oil is a modified form of neem where most of the Azadirachtin is removed for use in chemical pesticides.
It comes in concentrations of .5 to 3% percent Azadirachtin content.
We strongly suggest using the .5 to 1% percent for orchids to reduce the risk of burns.
Clarified neem is most often used in foliar sprays due to its gentler nature and suffocates any bug it coats.
Using a Neem Foliar Spray
To make the foliar spray, first mix 1 teaspoon of pure castile soap per gallon of warm water.
NOTE: Avoid Dawn dish soap for orchids, as this may damage the wax if you use too much.
Stir 4 teaspoons of clarified neem into the mix and pour into a spray bottle.
We suggest using .5% percent as a preventative and 1% percent for most infestations.
Unless the infestation has spread to the flowers, try to put a piece of cardboard in front of them while spraying and work from the top down.
This will protect the flowers of more sensitive species while still getting most infestations, although thrips and a few other pests may also attack the flowers.
Repeat every other day for 14 days or until the infestation is gone.
Simply break up the neem cake and apply as instructed.
Remember that the cakes have NPK and are considered a fertilizer, so be sure to adjust your regular orchid fertilizer as needed to keep the proper NPK totals.
Neem Soil Soaks
Neem soaks can last up to 22 days in the plant and won’t harm the wax coating or flowers. However, potting mix soaks are not the best option for some orchids due to their epiphytic qualities.
To mix, make an emulsion using 1 teaspoon of Dawn dish soap or pure castile soap, then add 2 tablespoons of raw neem oil.
Pour 2 to 3 cups of the mixture onto the soil directly over the roots, covering a roughly equal radius of the root spread.
Avoid splashing the plant itself.
The neem will kill ground pests as it soaks down without harming earthworms and will be absorbed by the plant to become a systemic insecticide that doubles as a partial fungicide with antibacterial properties.
Reapply every 14 to 21 days at watering time as a preventative or until the infestation is gone.
Neem oil is non-toxic to humans and pets, but you should still wait one day after treatment before making a bouquet, just if the recipient has an allergy or sensitivity to neem.