Why Are My Aloe Plant Leaves Sticky?

The Aloe genus has over 500 species and tons of gorgeous varieties. These succulents have become one of the world’s most common houseplants. From their thick and sometimes colorful leaves to their nutrient-dense sap, gardeners love them for many reasons. 

On top of all their uses, they’re super easy to grow and need little maintenance. However, as beginner-friendly as they are, they still succumb to problems. One of the most common issues with aloes are sticky leaves. 

Sticky leaves don’t necessarily mean your plant is in trouble, but it’s important to find out what’s causing it. Below are the reasons why your aloe plants’ leaves are sticky and what to do to help them. 

Mealybugs

Mealybugs are common pests found in gardens and houseplants around the globe. As resilient as your aloe plants are, they’re not immune to these pesky critters. They are tiny, around 3mm long, and infest the stems, leaf nodes, and undersides of your plants. They appear as white, cotton-like dots on the leaves. 

When these teeny creatures consume your aloe’s sap, they leave an excrement on the leaves called honeydew. It’s full of sugars and other organic compounds that cause it to feel sticky to the touch. 

If you think mealybugs are making a meal out of your leaves, it’s time to get rid of them quickly. First, try rubbing your succulents with less than 70% isopropyl alcohol and water. Use a cotton swab dipped in the solution and rub it on the insects to remove them. This should do the trick if the mealybug infestation isn’t too bad. 

If the infestation is too severe, you’ll have to try other measures. Try using a non-toxic pesticide such as neem oil or insecticidal soap. Put on gloves and spray your leaves according to your product’s directions. Spray the infected areas down with water and keep monitoring them to make sure the infection is gone. 

Aphids

Aphids are one of the most common pests for your aloe plants. They are troublesome and literally suck the life out of your houseplants. They also spread diseases that can kill your succulents. These tiny insects can go from a small problem to a huge infestation in a split second. This is because females are usually already pregnant when they’re born. 

There are over 4,400 species, and hundreds that are common in gardens across the US. They are small and sometimes hard to see, but if you look carefully, you’ll find them. Like other small insects, they secrete a sticky honeydew as they feed on your aloes. 

One aphid to look for is the Aloe vera aphid (Aloephagus myersi). Its body has a waxy white covering. This species produces a lot of honeydew, which can lead to fungal infections such as sooty mold. 

Fortunately, there are several effective ways to rid your succulents of aphids. Try using horticultural soaps to wipe the sticky, infected aloe leaves. Castille soap and water solutions are also very effective. Repeat the treatments daily until the troubling bugs are completely gone. 

Scale Insects

Like mealybugs, scale insects can cause a lot of issues and leave your leaves feeling sticky. As these tiny bugs feed on the sap, they secrete honeydew. Scale honeydew is also full of sugars that stick to your leaves. 

These insects are around 0.1 inches and oval-shaped. Scale insects can be a bit harder to detect than mealybugs or aphids. One of the best ways to rid your plants of them is by using a cotton swab or Q-tip soaked in 70% or less alcohol. Follow up by spraying neem oil. 

There are several species of scale to look out for. Below are a few common scales that can infect your aloe plants.

Diaspididae

Diaspididae are also called armored scales because of their protective coverings that resemble shields. There are over 2,000 species, which makes these tiny pests some of the most prevalent in gardens. 

Hard scales are easier to identify than soft scales. They usually have dark-colored shields in clusters on the leaves. You’ll see a white, cotton-like substance around the clusters of male insects. 

Coccidae

Coccidae scales are called soft scales because of their soft, waxy coating. This is their way of protecting themselves from predators and angry gardeners like you who want them gone!

They usually flatten themselves on the surface of their hosts. They can sometimes blend in with the color of your plants. This makes them hard to see and identify.

Brown soft scale is one of the most common coccidae on aloe plants. They appear oval and light green, yellow-green, or light brown. The immature scales, known as crawlers, are yellow. 

Spider Mites

Spider mites are other web-producing pests that can live on your aloe leaves, causing a sticky texture. These microscopic insects will suck the sap from your succulents and leave the webs on their leaves as they grow in number. 

They are so small, you won’t be able to see them. However, huge colonies will form on the underside of your aloe leaves.  

You can prevent spider mites by encouraging beneficial insects to your garden or houseplants outdoors. Plant nectar-producing plants that attract predatory wasps, lacewings, pirate bugs, and lady beetles. Other options include washing your plants with high-pressured water or spraying them with a plant-based insecticide or soapy water. 

Sooty Mold

After secreting honeydew on your leaves, another sticky problem can arise: sooty mold. This type of mold comes from several species of fungi that grow from honeydew. They form dark patches of mold, which look horrible. 

On top of being sticky and unsightly, sooty mold can prevent photosynthesis, leading to withered leaves. It won’t kill your succulents, but it will look pretty nasty. If you leave it untreated, it can cover other plants and even fall on your floor or get on your clothes. There are a few garden issues more annoying than sooty mold stains. 

This fungus feeds on the sugars in the honeydew. If you have an infestation of aphids, mealybugs, or scale insects, there’s a chance you’ll get sooty mold eventually. That’s why treating these tiny insects is the first step to preventing sooty mold from infecting your succulents. 

Steps to Get Rid of Sooty Mold

As mentioned before, the best way to rid your plants of this sticky infection is to get rid of honeydew-producing insects first. This is the only way to prevent the mold from forming. 

Aside from stopping sap-sucking pests in their tracts, there are a few ways to eliminate the infection. First, try washing off the mold with high-pressure water. Your aloe plants are tough and can handle a little force from the water. 

If that doesn’t work, try wiping it off with a damp or soapy rag. This should clear the mold away. Repeat until all the mold is gone. 

Chemical Residue

Some household chemicals, fertilizers, and other sprays leave sticky residues on our succulents. If your aloes are free from pests, the sticky substance could be from chemicals. 

If you use household cleaners near your houseplants, they can accumulate on the leaves. After a while, these chemicals form a sticky substance. Everything from simple soaps to window cleaners can leave residues. 

If you haven’t used cleaning products, the culprit could be from the outside. Outdoor specimens could be downwind of people or companies using chemical sprays. If this is the case, you’ll have to move your succulents to another location in your garden. 

Another Plant’s Sap

If, after searching your plant for infestations or diseases, you still can’t find the culprit, it’s probably another plant’s sap. Ok, this may sound silly, but given where aloe plants thrive, it makes sense. 

These succulents do best in warm and dry regions such as California, Arizona, and Texas. Other plants that thrive in these regions include several species of pines, eucalyptus, and olives. These plants produce sticky and aromatic resins as defense mechanisms against pests. 

If your aloe plants are growing under or beside these trees, they can get the sticky sap on them. Not all these trees have aromatic oils in their sap, so it can be tricky to identify them. Check the trees near your succulents to see if they’re producing sap and consider moving your aloes away from them. 

Another way your aloes can get sap on them is from your garden tools. As annoying as sticky sap can be, it can transmit diseases and pests to your aloes. Always thoroughly clean your garden scissors and shears after using them.