How To Treat Scale Insects On Houseplants

Despite your best efforts, nature will occasionally take its course and you will need to regard your plant as a scale. The backside of these small insects’ shells reveals that they have securely attached themselves to your plant and are actively draining its sap away, despite the fact that they can resemble benign brown growths on your plants.

Scale can be any color, shape, or size, but it most frequently takes the form of small, brown, spherical lumps on the leaves and stems of your plant. There are two basic categories of scales: unarmored or soft scales and armored or hard scales. The names allude to the insect bodies’ protective shell-like covers. The protective scale that the insect is covered with makes control difficult, as it is with mealybugs. Scales can be round, oval, or oyster shell shaped, and they can be up to 1/8 inch long. They are primarily brown in color, but they can also be white or black.

Under their shells, females can lay hundreds of eggs, which hatch into 1/100-inch-long, translucent worms. The initial few seconds of a scale’s life are spent moving around until they cling onto a plant’s leaf permanently. These defenseless crawlers, however, go on to fresh feeding grounds where they affix to the plant and create their own protective shells. Since it’s uncommon for a plant to have only one scale, there probably are more lurking beneath the surface. Treat your plant as soon as you see any symptoms to save it from becoming overwhelmed.

The safest way to start treating scale, whether it has a soft or hard shell, is to start by removing the pests with your fingernail, a soft toothbrush, or even a Q-tip bathed in rubbing alcohol. Soft shell scale bugs can be receptive to insecticide. Most can be easily taken off the plant with a little bit of push, while tougher adults can sometimes be more resistant. To get rid of any stray bugs you may have plucked off but dropped into another area of the plant, rinse the plant under the sink or shower faucet. While doing so, take care not to moisten the soil excessively.

In order to treat any remaining larvae, the next step is to apply an insecticide. It’s crucial to treat the entire plant with your selected insecticide even if you manually removed every bug because the larvae are so minute they may still be present. Neem oil is recommended as an all-natural, organic therapy and preventative measure, but insecticidal soap may be more effective for severe infestations. Simply use either mixture to evenly mist the entire plant from top to bottom, then use paper towels to clean the foliage. Please take note that sunlight mixed with the insecticide might burn a plant, thus insecticide should only be used at night or when the plant is out of direct sunlight.

a severe infestation of scales. Notice the buildup of scale close to the stem, which is the leaf’s juicier and more nutrient-rich area.

While it heals, keep the afflicted plant separate from the rest of your collection, taking extra care to make sure that none of its leaves touch those of any other plants. Continue using this method every 7 to 10 days until the scale bugs stop appearing. Make sure to periodically and completely inspect all plants for future prevention. A nice addition to regular plant maintenance is dusting leaves and checking for pests.

How can scaling on indoor plants be removed?

There are several strategies to manage scale insects in the garden, but the best ones involve preventive or eliminating contaminated plant material before the insects can spread. Even though you might not need to take all of these actions, you could need to combine them in order to get rid of a scale bug infestation.


If you find the infection when it is still little, pruning diseased branches is frequently the simplest and safest solution. Make sure you have removed all infected stems by carefully inspecting the plant and any nearby plants. Infected plant debris should not be composted; instead, it should be bagged and properly burned or disposed of in the trash.

Treat With Rubbing Alcohol

If there is a light infestation of scale insects, rubbing alcohol can destroy them. The best strategy is to use a cotton swab to apply the rubbing alcohol directly on the scale bugs. However, doing this in an outside garden can be quite time-consuming. As a result, you can also prepare a solution of one part rubbing alcohol to seven parts water and put it in a garden sprayer or spray bottle.

What is horticultural oil?

Most horticultural oils are petroleum-based mineral oils, while some vegetable oils, such cottonseed and soybean oils, also have pest-repelling properties. In order to make oil easier to spray, it is typically emulsified.

Spraying horticultural oil on your plants in the late spring, right before the leaves emerge, is useful. Scale insects have the ability to hibernate as nymphs or eggs hidden in tree bark.

At this stage, spray your plants using 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 on stems, the undersides of leaves, and along the base of the plant, thus it’s crucial to treat the entire plant. The scale insects are suffocated by the oil, which coats them and obstructs their breathing pores.

Apply Insecticidal Soap

Scale can be killed using insecticidal soaps while they are still larval, but once the insects are attached and foraging inside their protective shells, they are less effective. Use a garden sprayer or spray bottle to apply until all of the leaves are dripping.

Follow the instructions on the container to be sure, but generally speaking, 1 ounce of soap to 1 gallon of water is a reasonable ratio.

These soaps don’t withstand the weather for very long, so multiple applications will be necessary to catch all the larvae, but these organic insecticides won’t leave a risky environmental impact.


Apply insecticidal soaps only to well-hydrated plants to avoid hurting them. Never use the product on plants that are exposed to direct sunlight or when it is hotter than 90 degrees Fahrenheit.

Apply Neem Oil

Neem oil and other insecticides containing azadirachtin, a fundamental component of neem oil, provide great defense against scale and kill adult insects as well as merely larvae.

Neem oil and water don’t mix well, so you’ll need to add some dish soap to serve as an emulsifier. As a general rule, add 1 to 2 teaspoons of oil and 1 to 2 tablespoons of detergent to each gallon of water. Use a garden sprayer to apply.

Since honey bees and the majority of other helpful insects are not poisonous, neem oil and other treatments containing azadirachtin are recognized as organic insecticides. It is possible for other plant-based insecticides to be effective.

Use Beneficial Insects

Scale insects can be effectively controlled by beneficial insects including lady beetles, soldier beetles, and parasitic wasps. 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.

In the fight against scale, synthetic chemical pesticides ought to be the absolute last option. Neoicotinoids (acetamiprid, dinotefuran, imidacloprid, and thiamethoxam), which are present in systemic insecticides and can be used with some success, are increasingly recognized as a severe threat to honey bees and other pollinators. A chemical pesticide should only be used when all other options have failed.

Controlling Scale on Indoor Plants

Scale insects will proliferate even more quickly indoors than they do outdoors because there are no natural predators there. When scale infests indoor plants, you will need to be incredibly meticulous about controlling or removing it.

Pruning out the infected stems could solve the issue if you find it early enough. For a few weeks, keep a close eye on the plant to make sure no new scales develop. Throw away the pruned stems right away.

Gently brush existing scale off of indoor plants using a cotton swab or facial-quality sponge coated in rubbing alcohol. The scale should be killed by the alcohol on its own, but the dead insects will stay on your plants and make it challenging for you to look for fresh 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 choose plain sponges free of lotion or cleansers. A limited area should always be tested first because certain plants are more sensitive than others.


For two to three weeks, keep new houseplants separate from other plants in order to check for the appearance of scale. Until the treatment is finished, isolate the infected plants.

Remove pests:

Use a soft toothbrush or cotton swab dipped in soapy water or 70% isopropyl alcohol to gently remove scale from smaller infestations. Because some plants can be sensitive, test a small area first. Every few days, check the plants, and repeat the treatment if necessary.

What They Look Like

Scale are tiny, reddish-brown, flat insects that feed on plant liquids and leave a sticky film on leaves as a result. Scale insects mature into a hard, rounded shell that can make them challenging to eradicate.

Green Thumb Tip

Regularly inspect your indoor plants, and cure any infestation as soon as you see it.

Invading other plants and rapidly reproducing, bugs can spread fungal or other diseases from one plant to another.

The majority of scales are found connected to stems and the undersides of leaves, typically along the major veins. You could observe that the damaged portions become feeble and yellow. Ficus and ferns are greatly bothered by scale.

These insects exude honeydew after sucking on plant fluids. This sticky substance is present on the plant’s leaves as well as on the ground or a nearby table.

How to Get Rid of Scale Insects

Spraying some soapy water on the young scale insects usually works to suppress them. Use gentle dishwashing soap without fragrances or other chemicals. To 1 gallon of room temperature water, add 2 teaspoonfuls. Spray the soapy water onto the leaves and stems using a spray bottle to completely cover them. For at least a month or until you can locate no more insects, spray once every week. Always completely rinse the soapy mixture off with warm water.

It can be more challenging to get rid of adult scale. If spraying doesn’t remove them, scrub them off with an old toothbrush dipped in soapy water. Areas that are heavily infected should be trimmed.

Numerous household pests, including scale, are killed by rubbing alcohol. Use a cotton swab dipped in rubbing alcohol to wipe them down. Apply again every two to three days. Use this with caution even though it works effectively. Plant tissue is harmed when alcohol is applied to the entire leaf.

The label for the product lists your plant. Follow the manufacturer’s usage instructions after carefully reading the label.

What results in scaling on house plants?

Although these tiny insects can come from a variety of sources, scale on your indoor plants can seem to appear overnight. Maybe you reused a soiled plant pot, used contaminated potting soil, or left your plants outside during the warm months. You must get rid of the infestation as soon as you discover scale to prevent it from getting worse.

Scale insects can be difficult to control since they often withstand most pesticides. Avoid wasting your time on dangerous chemicals that cannot pierce their thick exterior. Even though it can take some time, it’s worthwhile to remove stubborn scale in order to restore the health of your plant. Learn how to remove scale from indoor plants by reading on.

How do indoor plants get scale?

According to an Army Corps of Engineers report, over half of the expansive marshland in the lower Mississippi River Delta has withered or died recently.

As newly hatched crawlers, which are quite tiny, have legs, and can move around, scales spread from plant to plant. With the use of readily accessible contact insecticides, crawlers can be controlled pretty easily. Scale crawlers can be challenging to find, unfortunately. The majority of gardeners overlook them and lose the chance to exert control.

In the spring, many scales generate crawlers. Insecticides applied directly to the crawlers lose most of their effectiveness once they have settled down to feed and have formed their protective covering.


In general, scales are not one of those insect pests that will simply disappear over time if you ignore them. Most of the time, control is required.

Oil sprays are the most eco-friendly and efficient pesticides for controlling scale. Oil is present in these insecticides in a form that will mix with water. The oil coats the scale insects and blocks their breathing pores when combined and sprayed onto an affected plant. Instead of being destroyed by a toxin, the insects suffocate.

Heavy oils like Volck Oil Spray and light oils like Year Round Spray Oil, All Seasons Oil Spray, and others are marketed under specific brand names. The fact that mild horticultural oils can be used all summer long is why I enjoy them.

It is essential to spray the oil on all surfaces of the plant for effective control. The oil won’t affect the insects if they are on the underside of the leaves and the oil is just sprayed to that surface. Due to the difficulty in getting rid of scales, the label’s instructions should be followed for a second and even third application.

Aphids, whiteflies, spider mites, and the crawling stage of scales can all be successfully controlled with oils. Oil sprays do not leave behind a residue that can harm beneficial insects, in addition to having a low toxicity.

Oil sprays also assist in cleaning the plant of the ugly sooty mold, which is an added bonus.