In normal conditions, succulents aren’t particularly attractive to various bugs and pests. Insects prefer other plants that are easier to attack, and offer a more delicious sap. However, in the midst of a rainy season, or in generally damp and humid conditions, or if you (no doubt unwittingly) over-water your succulents, you can spot tiny black bugs on their leaves and stems. In rare cases it can also happen in normal dry conditions, for example when bugs jump from a previously infested plant on your succulent. But what exactly are these tiny insects and how can you get rid of them?
Before we dive into important details, let me give you a quick answer to the question: The tiny black bugs on your succulents are most likely fungus gnats (also known as sciarid flies), less like aphids (most prevalent aphid species have green color, but we know more than three thousand aphid species, and some have black color), and even less likely ants, which many people with bad eyes may easily mistaken for bugs. Let’s have a look at each of these pests, and how you can deal with it.
Fungus gnats as the no. 1 most common tiny black bugs on succulents
Fungus gnats thrive in moist and damp conditions. But it doesn’t mean that they do not appear in dry climate. Actually they do not need much–a couple of succulent pots with moist soil, or a compost ground nearby, or a rotting plant near the succulents. What I try to say here is that a fitting micro-climate is enough for them to settle and start breeding. And they can find your succulent pot such a micro-climate.
These gnats, often also called sciarid flies, aren’t particularly dangerous on their own, but having them on your succulents signalizes a bigger problem. You are most likely over-watering your plants. Unless you stop soon, you will lose your succulents to root rot and consequent death of the plant.
My best advice in this case is amending the watering schedule, or even repotting the plant to a well-draining succulent soil, throwing the old soil away (since there are almost for sure eggs of these gnats in the soil). If you do not feel like repotting the plant (for what-ever reason), you can try sprinkling the leaves with a soap and water mixture repeatedly. Pouring cinnamon powder on the soil may also help, but cinnamon is expensive so I am not sure if this is a best solution. If you want to be 100% sure, repot the plant, throw the old soil away, adjust watering schedule, and most likely the fungus gnats will simply disappear from your succulent.
Black aphids as no. 2 most common tiny black bugs on succulents
Aphids often appear on plants for no apparent reason. If you have an outdoors garden, and it isn’t a permaculture establishment (where natural enemies of aphids thrive), you may easily find aphids on half of your plants (of any kind, including fruit trees, vegetables, or succulents). Aphids feed on plant sap and excrete a sugary substance that attracts ants and other bugs. Hence ants often follow aphids, and the problem only intensifies…
Except of having a permaculture garden with huge variety of plants and trees and dozens of insect and animal species that naturally feed on each other, there’s no sure way of avoiding aphids on your succulents. If they appear indoors, however, wet soil or humid conditions are typically to blame, and you should make sure to improve the growing conditions of your plants. We have an entire article online on the topic of aphids on succulents, and how to deal with them with home-made remedies, so check it out if you identify aphids as your problem. Onion-garlic spray, mixture of baking soda and vegetable oil, or even a simple dish-washing soap are just some of the remedies.
Ants as no. 3 most common black “bugs” on succulents
Ants technically aren’t bugs, but it is easy to mistaken them for such, especially if you do not have the best eyes. In many countries around the world we experience something we can call an “epidemic of ants”, and it poses a serious threat for gardeners and plant growers. Just like with aphids the causes aren’t exactly clear, but the most common cause is climate change, which puts a dent to the balance of our natural ecosystems. Ants lose their natural enemies, and suddenly they are almost everywhere!
Ants are hard to defeat, since they are smart, their cooperation is excellent, and the pure quantity of them can overwhelm any enemy. Once you have ants in your house or garden it isn’t easy getting rid of them. Sure enough, you can put sticky ant traps on the stems of your plants and trunk of your trees. But this will always work just to some extent, and some ants will reach the plants anyway. I have to advocate for permaculture again. Having a variety of plants and trees in your garden, and plenty of naturally occurring insects and birds in your garden is the best prevention from the “epidemic of ants”. Anything else will be an endless fight.
In normal conditions succulents aren’t particularly attractive to bugs or other insects. However, in the midst of a rainy season, or when you over-water your plants, or when you simply do not have right balance in your garden (in terms of plants, insects, and animals), tiny black bugs may appear on your succulents. As you know now, in most cases it goes about fungus gnats, black aphids, or black ants.
It isn’t always easy to deal with these pests, and you have to be patient. Spraying the plant once with a homemade remedy will rarely do the trick. You have to repeat the procedure several times, and even then it may not work. With fungus gnats repotting the succulent (and less frequent watering) will often help, but with aphids or ants it is more about managing the problem than completely eliminating it. Hope this helps, and I wish you good luck with your succulents!
May also interest you: Can succulents die of old age?