If your succulents are covered in little white crumbs, it isn't because your significant other was eating crackers over them. The problem is more likely mealybugs , a species of scale. And, they are the most common pest that infests succulents.
Eliminating mealybugs can be a daunting challenge, but there are some good strategies you can use to try to protect your succulents from further damage. Read on for tips on how to identify and eliminate mealy bugs on succulents.
Disclosure: We may receive commissions when you click our links and make purchases. This does not impact our reviews and comparisons. All opinions are our own. We pride ourselves on keeping our articles fair and balanced. For more info see our disclosure statement.What Are Mealy Bugs?
If you've ever tried growing citrus, gardenia, or camellia, you've probably encountered armored scale. Mealy bugs are also a type of scale, known as "soft scale." However, they don't look anything like their waxy cousins, but they are equally big problems for your houseplants.
Both mealy bugs and armored scale (as well as aphids) are sap-sucking insects. They impale your plant's leaves with needle-like mouths and suck out the juice. After digesting it, they excrete a sweet, shiny, sticky waste substance called honeydew. Honeydew attracts ants, fungus, and plant viruses.
Note: It is possible for mealybugs to infest both indoor and outdoor succulents. However, they prefer warm, consistent temperatures, so they are much more likely to infest indoor succulents.
How To Identify Mealy Bugs
If you spot them quickly, mealy bugs aren't too hard to manage, but unfortunately they like to live in hidden places on plants. Part of the appeal of succulents to mealy bugs is that they have so many crevices, nooks, and crannies, many of which are not visible to you because of tightly packed leaves, such as on a Sempervivium. That means that by the time you notice your first sign of mealybugs, you may have a full-blown infestation.
There are many sub-species of mealy bug. Generally, the type of mealy bugs that may infest your succulent is tiny white insects (typically 1-3 mm, or less than a tenth of an inch). Only the males have wings, which might seem unfair until you learn that they don't have any mouths, so they die after only a couple of days (their entire function in life is to fertilize the females and make more mealy bugs). The males are often described as looking like gnats, while the females are often said to look like crumbs.
Signs of Mealy Bugs on Succulents
There are many signs that point to a mealybug infestation even if you don't actually see any mealybugs.
White Stuff On Succulent Leaves
Rather than seeing individual bugs, you might see a white, lumpy substance that looks like lint on your succulent. This is either the bugs themselves (many mealy bugs create a coating or tail out of a white waxy substance that they wear like a coat or drag around like a tail) or it could be egg sacks full of baby mealy bugs. Either way, it's a clear diagnosis.
Honeydew
If you see a clear, sticky, shiny substance on your plant that looks like little drops of sugar syrup, you may have mealy bugs. That substance is honeydew, a waste product created by aphids, armored scale, and soft scale-like mealybugs. Fortunately, most of the strategies you'd use to control mealy bugs will help regardless of exactly which of those insects is infesting your succulent.
Ants
Ants love to eat honeydew so much that they will actually transport mealybugs or scale into your house and deposit them on your succulent in order to eat their excrement later. Yes, the ants are farming mealybug poop. If you do see ants on or near your succulent, and you don't have mealybugs yet, expect that you might get them soon.
Sooty Mold
Sooty mold loves to grow on honeydew. If you do see evidence of a black mold, you may as well adopt a mealy bug treatment protocol. Neem oil in particular is a great organic product that is a simultaneous insecticide and fungicide. You could also try these recommendations for addressing sooty mold.
Sickly Leaves
Occasionally, if you let the infestation get really bad, and the mealy bugs have lots of time to feed, they may suck so much juice out of your plant that the leaves start showing signs of depletion. They may become soft, deformed, or yellowish.
How To Get Rid of Mealybugs on Succulents
You have several options for addressing a mealybug problem, from more conservative treatments (optimizing your plants health and keeping it clean) to more extreme measures (such as pesticides).
Which approach you should take depends on the severity of the infestation, but in most cases, a combination of strategies will work best. We recommend you focus on your plant's health and tidiness, and choose one of the other options to try.
Optimize Plant Health
Healthy succulents are rarely infested with bugs. It is always possible, of course, but it is far more likely that your plant is sickly and vulnerable. And, that all comes down to your maintenance habits.
One of the most important steps is learning to water your succulents correctly. Overwatering (or poor drainage) results in root rot, encourages the growth of fungus and creates conditions that make your planter a hospitable home for pests.
Sometimes the problem is not too much water but too little drainage. Choosing the right pot for your succulent is essential if you want a healthy succulent.
Aside from pot and water, there are other factors that can influence your succulents' health and susceptibility to pests. These factors include the amount of sunlight, temperature, and the composition of your potting mix.
For more information on how to make these factors work for you, not against you in your fight against mealy bugs, you'll want to read our complete guide to growing healthy succulents.
Clean Up Your Planter
Just like sickly succulents, messy succulents are vulnerable to pests like mealy bugs. While it's tempting sometimes to leave your succulent to clean up its own room, just like toddlers and teenagers, they sometimes need a little help keeping everything in order.
One of the most important preventative measures you can take is to remove dead leaves that have fallen off of your succulent. If you're dealing with an infestation, you may also want to remove the dead leaves from the base of your succulent before they fall off.
Info: Dead leaves encourage mold formation and create dark moist hiding places where insects like mealy bugs prefer to reproduce.
We tend to think of soil as intrinsically dirty, but the truth is that you want "clean soil" in your pot, not dirty soil. By clean soil, we mean uncontaminated soil. The best practice is to repot your plant in fresh potting mix (you'll find our recipe here) as soon as you bring it home, and never reuse potting mix. Especially avoid reusing soil from a plant grown in a home or business where any of the plants have any sort of disease or pest problem, including mealy bugs.
Note: If you want to be really careful, it is also a good idea to keep contaminated soil out of your compost pile (if you plan to use that compost as an ingredient in your potting mix in the future). Depending on how hot your compost gets, insects or eggs could survive the composting process and then re-infest your plants when you use the compost.
Eliminate Ant Access
You might have purchased a clean plant and kept it in a healthy state but you still ended up with a mealy bug infestation. One possibility is that ants literally carried mealy bugs into your house and dropped them off on your succulent, in the hopes of harvesting honeydew later.
If you think this may have happened, you should make an effort to stop the inflow of ants into your house so that the problem doesn't recur. There are many ways to address an ant problem. Start with these suggestions from the Oklahoma State University Extension Office.
Isopropyl Alcohol Spray
One of the most common and effective methods for addressing mealybugs is isopropyl alcohol.
Make sure to use 70% isopropyl alcohol (such as this option). We recommend diluting your isopropyl alcohol to 50/50 with water. Some gardeners recommend a mixture as low as 25% alcohol to reduce the risk of damaging your plant.
You can use isopropyl alcohol in one of two ways.
- Q-Tip Method: This method is ideal if you have a minor infestation or if you have a leggy succulent. It allows easy access to all sides of the leaves and stem. Simply soak the end of a cotton swab or cotton makeup removal pad in the diluted alcohol and wipe the plant down, focusing on the area of infestation.
- Spray Bottle Method: The second method is quite a bit more aggressive but may work better for you if you have a bad infestation or tightly packed leaves. Pour the diluted alcohol into a spray bottle, and spray the plant thoroughly. You may need to spray from a variety of angles for the alcohol to permeate tightly packed leaves.
Before using a lot of alcohol on your succulent, apply it on an expendable leaf (perhaps an offset, or a leaf that is missing a chunk and wait a day to see how it reacts. This is because alcohol may break down your succulent's waxy coating.
Regardless of which method you use, you will probably need to treat the plant several times - unless you notice the bugs early (before you have a full-blown infestation)
Note: Although alcohol is less dangerous than many chemical pesticides and will evaporate relatively quickly after use, it is not considered an organic method. It will kill beneficial insects, but that is not a real issue with indoor plants and is a minimal problem with outdoor plants given that the alcohol evaporates.
Ladybugs
Ladybugs may look cute, but they are actually merciless predators. More correctly named lady beetles, these beneficial insects are downright gluttonous when it comes to eliminating mealy bugs on succulents. Here's how you can use ladybugs to tackle your succulents' mealy bug infestation:
- Take your succulents outside to your garden (not too close to any susceptible plants, like citrus).
- Then, release a bunch of lady beetles in your garden (they are widely available and can be shipped, like this option).
This 100% non-toxic solution has a huge added benefit - it can also attack the aphids on your cabbage, snack on the scale from your Meyer lemon tree, and slurp up the spider mites on your perennials.
Lady beetles are a great alternative to using pesticides. In fact, you should avoid pesticides if there's any possibility you may want to use beneficial insects in the future. Most pesticides are indiscriminate and will kill the ladybugs you just released, and other important pollinators, along with the pest insects you want to target.
Insecticidal Soap Spray
Insecticidal soap is a solution preferred by many organic gardeners. It is made from plant oils and is otherwise known as potassium salts of fatty acids.
Insecticidal soaps are generally nontoxic to animals and are even safe for many beneficial insects. It kills mealybugs, scale, and aphids by suffocation and dehydration. This may sound harsh, but either they go or the succulent goes. Insecticidal soap spray also works well for removing honeydew and sooty mold from your leaves.
Keep in mind that you should dilute insecticidal soaps. Make sure to read the label of your bottle. For example, some insecticidal soaps have a dilution ratio of around 50 parts water to one part soap. While diluting it yourself is the cheapest option, it's also possible to buy a diluted insecticidal soap in a spray bottle.
Just like isopropyl alcohol, you need to spray it into all the nooks and crannies in your succulent where mealy bugs have hidden their eggs.
Note: Insecticidal soap can also remove the waxy coating from the leaves of your succulent. It's best to try it on a test leaf before spraying the whole plant. An excess of soap residue on your leaves can also cause phytotoxicity in high temperatures.
Neem Oil
Neem oil is another popular organic option. Some organic gardeners find it more effective than insecticidal soap. Neem oil is also a miticide and a fungicide, making it ideal if sooty mold is growing on your leaves. Like insecticidal soap and alcohol, you should dilute it before using it. Alternatively, you can buy it pre-diluted in a spray bottle.
The effect of Neem oil on your leaves will depend on the type of plant. So, perform a test leaf first.
Pesticides
Systemic pesticide sprays called neonicotinoids are also used to control insects like scale, aphids, and mealy bugs on succulents. This class of pesticides is chemically related to nicotine, but they are more commonly used on crops, not indoor plants.
As a matter of fact, they are very toxic and are a major reason for the dangerous decline of pollinating insects like bees, which is why they have been banned in other countries.
While killing pollinators is not much of a concern with indoor plants, there are other reasons to avoid neonicotinoids. These sprays are mildly toxic to animals other than insects, and can also damage your plant.
Because it is a "systemic pesticide" (meaning that it travels throughout the plant's vascular system rather than staying on the surface of the leaves like the other sprays), it has a greater potential to harm your plant systemically. Moreover, the dilution ratios recommended on the bottle may or may not be valid for succulents, which can be more sensitive than some other plants.
We recommend trying the other options before resorting to systemic pesticides.
The Sticky Truth about Mealybugs
There is no silver bullet for getting rid of mealy bugs on succulents. You will probably need to use at least three of the strategies (improving your plant's health, cleaning it up, and either lady beetles or a spray). You may even need to treat your succulent repeatedly.
If none of these methods work, you may just need to give up on the succulent. Get rid of it, and use it as an excuse to buy yourself a new one. Just remember to bury it in the trash, not the compost, so you don't re-infest your succulent with more mealy bugs down the road.
