As one of the most prevalent and harmful garden pests, scale insects can harm both indoor and outdoor plants. There are more than 8,000 different species of scale that exist, and they feed on leaves, stems, and branches, often causing extensive harm. Generally speaking, you can follow the steps below to get rid of the scale.
Step 1: Look over all of the leaves, stems, and branches for scale insects.
STEP 2: Cut away any scale insect-infested areas of the plant.
STEP 3: Apply a tiny amount of rubbing alcohol with a cotton swab to every visible insect.
Step 4: Use a soft, damp cloth to gently wipe away any dead scale insects.
STEP 5: To get rid of tiny scale larvae, spray the plant with neem oil or insecticidal soap.
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Why Do Scale Insects Exist?
Scale are related to aphids and named for the scaly or shell-like coating that protects their bodies, although there are also soft-shelled scale insects. They have a round, elongated, irregular, bumpy, or crab-like shape and are 1/8 to 1/2 inch long. Black, white, tan, amber, or yellow coloring options are available.
Males that resemble gnats have wings, are rarely seen and are unable to feed. Females lack wings and observable legs, making them immobile. It takes 1 to 3 weeks for the eggs, which are laid beneath the female’s protective shell, to develop into nymphs (crawlers). Nymphs are able to move, but they only make short trips before settling down to eat. As soon as feeding starts, the protective shell forms. Nymphs and females stay in the same place for the entirety of their lives.
Types Of Scale Insects
Scale bugs can be divided into two categories: armored and soft-shelled. Scales can also be malformed insects.
Armored scale (It is more difficult to eradicate Diasipidae because they are smaller and have a hard, flattened protective shell. Rather than indoor houseplants, they prefer to feast on outdoor trees and shrubs. There is no issue with sooty mold because the armored scales don’t produce honeydew. They can have 3 or 4 generations a year and have the ability to overwinter eggs, nymphs, or adult females.
Soft scales (Coccidae) are characterized by their larger size and rounded or oval dome shape, which resembles small turtle shells. They also produce a soft waxy protective layer. They are the kind that can be most frequently found in greenhouses or other enclosed spaces and secrete honeydew. One or two generations per year are typically produced on a soft scale.
How To Get Rid Of Scale On Plants
Controlling Scale On Indoor Plants
Since there are no natural predators inside, scale insects will proliferate even more quickly than they do outside. When scale infests indoor plants, you’ll need to be incredibly vigilant about preventing or eliminating it.
Pruning out the infected stems could solve the issue if you catch it early enough. For a few weeks, keep a close eye out to make sure no new scales develop on the plant. The pruned stems should be discarded right away.
Gently rub existing scales off of indoor plants using a cotton swab or facial-quality sponge dipped in rubbing alcohol. The scale should be killed by the alcohol alone, but the dead insects will stay on your plants and make it difficult for you to look for new infestations. The small facial sponges in the cosmetics section are small and soft enough to use without damaging the plant stems, but they are abrasive. Make sure to purchase plain sponges free of lotion or cleansers. A small area should always be tested first because some plants are more sensitive than others.
Controlling Scale On Outdoor Plants
The best way to control scale insects in the garden is to prevent them from spreading by removing infected plant material before they do3; however, you might need to combine some of these measures to be successful.
If you discover the infestation while it is still mild, pruning infected branches is frequently the quickest and safest solution. Make sure you have removed all infected stems by giving the plant and any nearby plants a thorough inspection. Infected plant material should not be composted; instead, it should be bagged and safely burned or disposed of in the trash.
Treat With Rubbing Alcohol
Rubbing alcohol can kill scale insects if the infestations are light. The best strategy is to apply the rubbing alcohol with a cotton swab directly to the scale bugs. However, doing this in an outdoor garden can be very time-consuming. As a result, you can also mix a solution with one part rubbing alcohol and seven parts water and use it in a garden sprayer or spray bottle.
Repetition is necessary every two to three days to completely get rid of the bothersome insects.
Spray With Horticultural Oil
Spraying your plants with horticultural oil is effective in late spring just before the leaves unfurl. Scale insects have the ability to hibernate as nymphs or eggs hidden in tree bark.
At this point, spray your plants with a garden sprayer or hose-end sprayer that is loaded with 2 to 5 ounces of oil per gallon of water. The scale will be smothered by this application before the insects can develop their protective coating.
Scale can be found along the base of the plant, on the undersides of leaves, and on stems, so it’s crucial to treat the entire plant. The scale insects are suffocated by the oil, which coats them and blocks their breathing pores.
Apply Insecticidal Soap
At the larval stage, insecticidal soaps can be used to kill scale, but once the insects are anchored and fed inside their protective shells, they are not very effective. Till all the leaves are dripping, apply with a spray bottle or garden sprayer.
Follow the instructions on the package to be sure, but generally speaking, 1 ounce of soap to 1 gallon of water is a good rule of thumb.
Due to the short shelf life of these soaps in the weather, multiple applications will be required to completely eradicate all of the larvae, but these organic pesticides won’t pollute the environment after use.
Apply Neem Oil
Neem oil, or any pesticides containing azadirachtin, a key component of neem oil, provide excellent defense against scale and also kill adult insects as well as their larvae.
Neem oil and water don’t mix well, so you’ll need to add some dish soap to serve as an emulsifier. Use 1 to 2 teaspoons of detergent and 1 to 2 tablespoons of oil per gallon of water, on average. Utilize a garden sprayer to apply.
Since honey bees and the majority of other beneficial insects are not poisonous, neem oil and other treatments containing azadirachtin are regarded as organic pesticides. Other plant-based pesticides can also be effective.
Use Beneficial Insects
Scale insects can be effectively controlled by beneficial insects like parasitic wasps, lady beetles, and soldier beetles. By giving these natural predators food and shelter, you can encourage them. Additionally, you can order helpful insects via mail to release in your garden.
Identify Scale Damage On Plants
Scale insects feed on a variety of plants, but the majority of species are drawn to particular host plants. Depending on the species, they may be discovered on the fruit, bark, stems, or leaves of plants. Scale are an annoyance to indoor and outdoor ornamental plants, and some of them pose a serious threat to edible crops.
Chewing damage: Scale insects damage cells when they extract plant sap from plants, depriving them of nutrients vital to their health and growth. Scale damage to plants can manifest as yellow, wilted, or dropped leaves, diminished vigor, stunted growth, dead branches, cracked bark, or imperfect fruit. Weaker plants are more vulnerable to damage from extreme weather, other pests, and diseases. Plants may perish in the worst circumstances.
Sooty mold: The top side of leaves is where sooty mold grows most frequently. The presence of ants, a black sticky coating on leaves and branches, and yellowing or ugly foliage are signs. Photosynthesis, which is necessary for plant growth and health, is hampered by this fungus disease.
How To Prevent Scale
Prevention is the best strategy for managing scale.
Keep Plants Healthy:
Plants that are healthy are more tolerant of diseases and pests. When it’s hot outside and there is a drought, make sure your plants are well watered.
Choose Plants Wisely:
Plant pest-resistant tree and shrub varieties. Consult your neighborhood garden center or extension service for more details as some scale types might be more prevalent there.
Keep The Area Clean:
To reduce the presence of insect pests, clear away debris from plant bases and keep garden areas weed-free.
Inspect New Plants:
Before bringing newly acquired plants home from the nursery, thoroughly inspect them to avoid introducing pests to other plants.
Check Plants Regularly:
The problem is easier to manage when it is discovered early. Make it a habit to inspect plants as you perform gardening tasks like watering, fertilizing, and weeding. Concentrate on cultivars that are most susceptible, and look at every part of the plant, including stem joints and the undersides of leaves, where scale likes to hide. Take note of the black, sooty mold.