When you find scale on plants, getting rid of them can take some time – but it’s not impossible! In this post, I will show you exactly how to get rid of scale on houseplants, FOR GOOD. Simply follow these organic houseplant scale treatment methods.
Sometimes it feels like all of the plant bugs on the planet are trying to attack my houseplants! Until a few years ago, I’ve never had to deal with houseplant scale before.
I have no idea where they came from, but one day I suddenly noticed a scale insect infestation on my goldfish plant. Gross!
But don’t worry, scale is not a death sentence for your plants! I’ve successfully descaled my houseplants, and so can you!
What Are Scale Insects?
Houseplant scale are gross looking things that suck the sap out of the leaves and stems of plants; resulting in stunted or deformed leaf growth, yellowing of the leaves, brown pock marks, and possibly leaf drop.
You will usually find houseplant scale hanging out on the stems and leaf joint of an infested houseplant, and along the veins of the leaves, but you could find them anywhere on a plant.
You may also notice sticky leaves on houseplants, on their pots, or around the area where the plant is sitting.
Sometimes this is one way to help with plant scale identification if you’re unsure. As they feed, scale insects excrete a sticky residue which is a common sign of an infestation.
What Does Scale Look Like On Plants?
Scale insects are very difficult to see on a plant. Even if you do notice them, scale bugs on houseplants look more like a weird growth than a bug.
They look like small brown dots or bumps, and they don’t move. Eek! To me, they look like scabs on a plant (and that’s seriously what I thought they were the first time I saw them, haha!).
They can be rounded, oval shaped or flat, and can range in size from barely visible to large bumps on a plant. Their color can range anywhere from brown to tan to white.
If the bugs on your houseplants are white and fuzzy and look more like mildew, those are mealybugs. Here’s how to get rid of mealybugs.
Scale bugs on plants like to cluster, so they are very noticeable once the population gets large. Like I said before, they don’t look like bugs so you probably won’t even notice them until your plant has become infested.
Different stages of scale insect life cycle
Houseplant Scale Insect Life Cycle
There are several stages to the scale insect life cycle, and the entire cycle takes about 7-10 weeks. It takes a few weeks for the eggs to hatch into nymphs (aka scale crawlers), and then another 6-9 weeks for the crawlers to mature into adults.
A scale crawler can move around on a plant (or migrate to surrounding plants!) and, once they find a good place to start feeding and mature into adults, they never move again.
Scale insect eggs and nymphs are tiny, so it’s easy to understand why most people will never know their houseplant has scale until the population has exploded.
Scale Damage On Plants
Scale insect damage can look like pock marks on plants like succulents and cacti, or it can be something as subtle as brown or yellow leaves on a plant.
Thankfully, the damage caused by scale insects is not as quick to occur or as devastating as it is with spider mites, but it can still look pretty bad.
If a houseplant scale infestation goes left untreated, the plant will eventually die; although it would take a long time, and a very large scale population for them to kill a large houseplant.
Related Post: How to Get Rid of Fungus Gnats In Houseplants Soil
Scale insect damage on cactus plant
Where Do Scale Bugs Come From?
When you discover scale on plant leaves, the first question you’ll ask is where the heck did they come from? Scale insects are very sneaky, and many times you will never figure out where they came from.
Indoor plant bugs can come from anywhere, so don’t go crazy trying to figure it out what causes scale on plants. But, here are a few of the most common places where they may have come from…
- A brand new houseplant that you recently brought home from the store
- Contaminated potting soil
- Reusing a dirty plant pot
- Moving your houseplants outside during the summer
- Fresh produce or cut flowers from the garden (or even from the grocery store!)
- An open window – the crawlers are tiny, so you never know!
Read more about how houseplants can get bugs here.
Houseplant scale and damage on my cactus plant
How To Get Rid Of Scale Insects On Houseplants
As with any plant pest infestation, when you find scale insects on plants, you will want to isolate the infested plant and begin treatment immediately.
I don’t recommend using a chemical scale pesticide, because houseplant scale are resistant to most pesticides.
They also have the ability to develop a resistance to any chemical pesticides they are exposed to on a regular basis. Plus, in most stages of their life cycle, pesticides won’t penetrate their hard outer shell anyway.
So keep your family and pets safe, and skip the toxic chemical pesticides on your houseplants. Below are some methods you can try that work great to treat houseplant scale insects.
You can learn even more about all-natural houseplant pest control remedies here.
How To Treat Scale On Plants
One way to kill and remove as many of the scales from the plant as you can is by using a cotton swab dipped in rubbing alcohol (you may need to pry some of them off using your fingernail).
In order for rubbing alcohol to be effective, it must come in direct contact with the scale insects.
This scale bug treatment method works very well for small infestations, and to get rid of as many of the large scale insects that you can so you can gain the upper hand.
As you work on removing scale from plants, be sure that you check every crevice of the plant, around the leaf and stem joints, and underneath all of the leaves.
They like to hide, so be sure to check the plant from a bunch of different angles too.
Also brush away a little dirt around the base of the stem to see if any are hiding there, scale insects could also be found on the roots of the plant.
Use rubbing alcohol to kill scale on houseplant
Make Your Own Homemade Scale Insecticide Soap
You could buy organic insecticidal soap, or you can make your own homemade insecticide for houseplants.
The plant scale spray recipe I use 1 tsp of organic mild liquid soap per 1 liter of water. Then spray it directly on the scale and on the leaves of your infested plant.
If your plant is small, you can bring it to the sink or shower and wash the leaves with this soap and water solution, gently removing as many of the scale as you can as you wash the plant.
Keep in mind that some types of soap can damage plants, so it’s best to test any type of spray on a couple leaves before you spray the entire plant.
Homemade scale insect killer insecticide soap
Using Neem Oil For Scale On Plants
Neem oil for houseplants is a natural insecticide for indoor plants, and it’s very effective for treating scale on houseplants. An added bonus is that neem oil has a residual effect to help with future pest prevention too.
You can buy neem oil concentrate for pretty cheap, and a bottle will last you a long time. If you do end up getting the neem oil concentrate, then you’ll need to mix it with a little bit of mild liquid soap to help the oil mix with water. Don’t worry, it’s easy, just follow the instructions on the label.
You can use a pre-mixed horticultural oil or hot pepper wax spray instead of neem oil as a plant scale treatment, and these also work very well to help get rid of scale insects.
Learn more about neem oil insecticide
Using neem oil insecticide for scale insects
More Tips For Getting Rid Of Scale On Plants
You can’t treat a plant once and expect to get rid of scale insects for good, you need to be persistent. Keep checking your plants a few times a week, and remove any new bugs that you see. Here are a few additional tips…
- Scale can hide in the soil of a houseplant, so if a plant is plagued by recurring infestations, you could try removing the top inch of dirt from the pot and replacing it with fresh potting soil.
- Crawlers can leave the plant, and then come back to infest it again. So remove the plant from the area and clean any crevices where plant pests could be hiding. Be sure check around the outside lip and inside edges of the pot and plant tray, and also the bottom of the pot for hiding scale insects.
- Trim any heavily infested leaves from the plant and toss them into the trash (outside of your home). Never trim all the leaves from a houseplant though.
- If you decide to repot a plant after treating it for scale, then be sure to sterilize the pot before reusing. Houseplant scale insects can hide on the edges or the rim on a plant pot, and can easily infest any plant that’s potted in there. Scrub the pot with soapy water, or better yet, put it in the dishwasher to sterilize it.
- Use a neem based leaf shine, a natural insecticide for houseplants, regularly until you are sure you plant is scale-free.
It’s hard to get rid of scale on houseplants the first few times you try, it will take several treatments. Even if you are able to kill all of the adults, the eggs and babies are tiny and easily overlooked.
There’s no doubt that fighting scale on indoor plants can be super frustrating, but it’s worth it to save your favorite houseplants.
If you’re struggling to get rid of bugs on indoor plants, my Houseplant Pest Control eBook is for you! It will show you exactly how to get rid of bugs on houseplants naturally, including houseplant pests identification, home remedies for plant insects, how to keep houseplant pests from EVER coming back, and much more! Download your copy today!
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Recommended Reading:
More About Houseplant Pests
- How To Debug Plants Before Bringing Them Indoors
- How To Get Rid Of Spider Mites On Houseplants, For Good!
- How To Get Rid Of Whiteflies On Indoor Plants, For Good!
- How To Get Rid Of Bugs On Houseplants
How do you get rid of scale on houseplants? Share your scale insects treatment tips in the comments below.
Helen says
I have scale investation on some of the plants in my room, it’s all over the wall, windows and the wood of my dresser. I did not know what they were before so I just scraped it off once and thought it might be from the vent but it came back. How can I get rid of them and make sure they never come back. Please help.
Amy Andrychowicz says
Wow, I’ve never heard of houseplant scale getting on the walls and woodwork like that! Yuck! Rubbing alcohol, soapy water, or really any kind of disinfectant cleaning spray that’s safe to use on those surfaces will kill them. I would scrub down everything to remove and kill them, then keep cleaning the area regularly until you never see scale again. If you have plants in the room, then that is likely where they’re coming from, so make sure you treat the scale on your plants using the methods above, or they will just keep coming back.
Joyce A Solomon says
I have a ficus that is about four feet tall. I have tried neem oil and horticulture oil but it doesn t seem to do anything to get rid of them. also they seem to only be on the side of the tree that is not directly facing the sun. any suggestions the tree is large.
Amy Andrychowicz says
Yes, scale can be difficult to get rid of. You have to be persistent, because you can’t kill them all with only a few treatments. It can take several months (or even over a year) to eradicate a heavy infestation on a large plant. So plan to keep treating it with neem regularly for the long term, even after all signs of the bugs are gone.
Angie says
Hi, you said that also the roots could be infected, in that case what is to be done, wash the roots and repot ?
Amy Andrychowicz says
If scale insects are on the roots, it would be at the top right under the soil, near the stem of the plant. Just brush away the soil right around the base of the plant to see if you find anything there. Definitely don’t repot your plant if it’s infested with scale though. That could further stress the plant, and won’t do anything to get rid of the bugs.
Diana West says
I’m so happy I found your website! There’s a wealth of information here that I’ve never seen before! I will definitely acquire your eBook. I have 1 quick and important question about removing a type of brown soft scale on the base of succulents. I used tweezers and/or a butter knife sharp. It will continue to grow upwards on the stems (or trunk on lg. Plants). Is this process harmful if will weaken the plant? Please advise.
Amy Andrychowicz says
Awesome, glad you like the website and the eBook! Yes, scale will harm the plant over time if left untreated. Though it’s good to scrape them off as part of your treatment routine, the eggs and babies are difficult to see. So, it’s best to use some other type of treatment (neem oil works wonders) to get rid of scale all together. Otherwise, you’ll just be picking off the adults, and you’ll never eradicate the infestation.