Succulents need minimal attention, growing healthy and well because they can retain water for nourishment. However, they are also prone to pests and fungal diseases. Scales, for instance, can ravage the plants by sucking the sap from the leaves and stems.
Scales on Succulents: What are They?
Scales are very small insects that range from ⅛ to ½ inches in size. Their color, texture, shape, and other features may vary depending on their species; there are almost a thousand varieties. Some species are oval-shaped or round and gray or light brown-colored. These insects belong to the Sternorrhyncha suborder that also includes aphids and whiteflies.
Scales are divided into two categories, soft and armored. Soft scales have soft, thin, powdery, cottony, or waxy layers that are not separated from the body. Armored scales have a hard, shield-like cover made up of shed skins and wax that conceals the body but is not attached to the body.
Soft scale insects are easier to treat since they have soft outer shells. The adult females are usually immobile and secrete a waxy substance that they use as a defense, called honeydew. Armored scales do not secrete honeydew but have thick outer coatings.
The female soft scales lay eggs in the spring while the armored scales lay eggs at the start of the summer season. The eggs hatch later in the summer and develop into nymphs that grow into adults at the start of springtime.
Symptoms of Scales on Succulents
You will know that scales are ravaging your plants if you notice small brown bumps on the leaves and stems. These bumps may be spread out or clustered together. The succulents will appear collapsed or deflated and look neglected or in need of water or nutrients. Weakened plants become more susceptible to infestations and diseases; if left untreated they could eventually die.
Another sign that scales are in your plants is the presence of honeydew, a sticky, sugary liquid that these insects excrete. The liquid also attracts other pests like ants and even bees. It can also promote fungal growth; dark, sooty, foul-smelling sooty mold may appear. You may also notice the appearance of black spots on the leaves.
How do I control and treat scales on succulents?
Some plant owners tend to take the shortcut when it comes to controlling and treating scales on succulents. However, plant experts note that before you try horticultural oils or homemade insecticides, you should first try removing the pests by hand.
Early detection will make this process less time-consuming. Simply scrape the insects from the plants using your fingernails or a dull knife.
Heavy infestations require a more aggressive approach, such as using chemical treatments. Common types of chemical treatments include isopropyl rubbing alcohol, soapy water, neem oil insecticide, and commercial horticultural oils. Be sure to isolate the infected plants from the rest of your plants.
How to use isopropyl rubbing alcohol for scale treatment
To get rid of scales on succulents, use cotton swabs or Q-tips and apply isopropyl rubbing alcohol directly to the insects. Some plant owners use the alcohol without diluting it, while some prefer mixing it with water. Spray the solution on the insects liberally.
How to use soapy water for scale treatment
The use of soapy water is also effective to get rid of scales. Simply fill a spray bottle with a few teaspoons of dish soap, add water, and spray it on the insects thoroughly.
How to use neem oil and commercial horticultural oil for scale treatment
To use these particular oils, you need to dilute them with distilled water. Mix about one tablespoon of neem oil or commercial horticultural oil with eight ounces of water. Mix thoroughly, place it in a spray bottle and spray the mixture on the plants at night time. (It could burn the plants if sprayed during daytime due to the sunlight).
To ensure that the scales are completely eradicated, repeat the treatment at least once a week. If the chemical treatments did not yield positive results, try to transplant the plants since the eggs and nymphs may still be in the soil and roots.
Remove the affected plants and spray the roots with soapy water or isopropyl alcohol. Keep the plants dry for a few days and repot them using a fresh succulent potting mix.
Succulents are popular for being hardy plants, but they are also prone to pest infestations. Scales on succulents can ravage the plants because the insects are attracted to the juicy sap of the leaves. However, these pests are easy to treat, especially when detected early.
You can remove or scrape them off the plants with your hands or a dull knife. Heavy infestations require chemical treatments done consistently to ensure that the pests are removed from the plants.
Image: istockphoto.com / Merinka