Soil mites are small arthropods that are less than 1/20 inch in size (1 mm) that may be found in your plant’s soil surface or burrowed a few inches below. There are over 20,000 types of soil mites that are of different colors but are usually red, white, or brown.
Soil mites are harmless to your plant. They do not attack the plant nor cause any damage. On the contrary, they feed on organic matter in the soil, aiding in soil decomposition and aeration, which is beneficial for plant growth!
However, soil mites can transmit diseases to humans. If you are worried about this, use gardening gloves when handling your plant, and wash your hands afterward. These steps are sufficient to reduce the risk of infection.
Nevertheless, you can choose to kill soil mites if they really bother you – we show you how in the steps below. 🙂 In this article, we discuss i) what soil mites are, ii) how to identify and kill them, and iii) steps you can take to prevent them from setting up home in your plant’s soil.
What are Soil Mites?
Soil mites are arthropods typically less than 1/20 of an inch (1 mm) in length. They have a hard exoskeleton and segmented body. These scavengers are attracted to decaying organic matter such as mold, wood, and moss.
These critters prefer dark, humid locations, choosing to hang out on topsoil or burrow a few inches below. They are usually red, white, or brown, and move quickly in groups. Surprisingly they have long lifespans — some live for up to 7 years!
So far, experts have identified over 20,000 types of soil mites, though the total number is thought to be well over 80,000.
- Oribatids are the most common type of soil mite, and they feed primarily on algae, fungi, wood, and leaves. Their love for wood means they also hang out on decks and patios. They have been nicknamed turtle mites because of their large turtle-shaped shell bodies.
- Mesostigmatas are free-living predators, which feed on smaller arthropods. Some types even feed on spider mites.
- Prostigmatas have many sub-types, which range from predators and fungal-feeding mites.
- Astigmata enjoy nitrogen-rich, organic environments often found on farms. They are parasitic.
- Gasamids are predatory soil mites that live in the nooks and crannies of bark, leaves, or soil. They eat organic debris and help break down plant matter.
Are Soil Mites good or bad?
Despite being a bit scary to look at when enlarged, soil mites are harmless to plants. In fact, having them around improves the soil’s health. However, they *may* be harmful to humans.
The main benefits of soil mites are that they help with soil decomposition and aeration, which improves the nutrition and fertility of the plant’s growing medium. Plants are therefore able to derive food from the soil more efficiently.
Contrary to popular belief, soil mites do not feed on the plant itself or attack its healthy tissue. In fact, the presence of soil mites indicates a healthy soil ecosystem! 🙂
However, they can become health hazards to humans because they carry germs or diseases. Soil mites can transmit germs to humans and carry the eggs of a tape-worm. Because of this, always wash your hands after tending to your plants!
If you find soil mites in your outdoor plants and you are not too bothered by these critters, our advice is to leave them be. However, if you find soil mites in large quantities indoors, you may choose to control the number of mites in your home.
How to Check if you have Soil Mites
Soil mites are an umbrella term for various critters with different appearances and characteristics, so there is no definitive way to determine their presence. However, there are a few signs that you can use to check if these bugs are present in your soil.
- Inspect your plants. Recall that soil mites are typically less than a millimetre long, so they may appear as tiny white, red or brown flecks moving across the soil or on the surface of the pots. You will have to look closely!
- Carefully scoop up some soil from the planter and place it on a white piece of paper to look for the mites. Use the zoom function of your mobile phone camera to identify the mites.
How to Get Rid of Soil Mites
To get rid of soil mites, you’d want to repot your plant in fresh soil and use a pesticide spray to ensure the mites are eradicated.
Step 1: First, water your plant until excess water leaves from the drainage hole. Watering your plant before repotting reduces the risk of transplant shock to your plant.
Step 2: Two hours after watering, gently remove the plant from its pot, being careful not to damage its roots. Remove excess soil from the rootball, gently using your fingers to loosen the soil.
Step 3: Remove the remaining soil from the bottom of the pot and dispose of it.
Step 4: Place the empty pot under cool running water. Wash your pot thoroughly with mild soap and wipe dry, noting that soil mites may attach themselves to the sides of the pot or under its rim.
Step 5: Add an inch of fresh soil or potting mix to your clean pot. Place the rootball on top, adding more fresh soil as necessary to secure the plant in place.
Step 6: Pour the selected pesticide solution into the plant’s topsoil.
There are a few types of pesticides that will work to remove these insects. Here are several options that you can use or make yourself:
- Store-bought pesticide spray.
- Cinnamon solution: mix 1 tsp of cinnamon in 4 cups of water and 1 tsp of mild soap. Wait 15 minutes to allow the cinnamon to settle.
- Neem oil and soap: here’s how to use neem oil as a spray or soil drench.
- Hydrogen peroxide solution: mix 1/2 cup of 3% hydrogen peroxide with ¼ tsp of liquid soap in 2 cups of water. The solution will start bubbling when poured into the soil. Don’t worry, this is normal.
- Garlic solution: mix four cloves of crushed garlic with 1 gallon of water. Leave to sit for four days and then add ¼ tsp of liquid soap.
- Diatomaceous Earth: Diatomaceous earth, or DE for short, is a granular form of fossilized shells. It is a white chalky powder that works by cutting up the soil mite’s exoskeleton upon contact, resulting in death for the insect. DE is effective against any insects that have exoskeletons. Dust some DE on the surface of the soil. Ensure the soil’s surface is dry, as moist soil reduces DE’s effectiveness.
How to Prevent Soil Mites
Soil mites can be difficult to get rid of once they become established. As always, prevention is better than cure. If you don’t want to deal with soil mites and other pests, a good option is to use LECA as a growing medium instead.
Because LECA is inorganic, soil mites are not attracted to plants growing in LECA. There are a couple of Pros and Cons to LECA to consider before making the switch – which we detail in our article here.
Otherwise, here are some other tips to reduce the risk of infestation:
- Remember to always wash your hands after tending to your plants to reduce the risk of transmitting germs.
- Regularly clean your growing area and remove any decaying organic matter, including leaves and rotting wood. If you remove their food source, these insects will move away on their own!
- Repot your plants occasionally in fresh potting mix.
- Before introducing new plants into the home, inspect them to ensure they do not have any soil mites.
- Move your outdoor plants away from your compost heap if you have one.
Frequently Asked Questions
What is the difference between Soil Mites and Spider Mites?
Spider mites are arachnids related to spiders and ticks, while soil mites are anthropods. Spider mites usually live on the leaves and stems of plants, while soil mites live on or under the soil’s surface. Despite both being called “mites”, they are not closely related!
The most significant difference is that spider mites are harmful to your growing plant, while soil mites are beneficial.
Spider mites are plant-eating mites that feed on the sap of plants. They cause dark-red spots on the plant’s foliage and damage its tissue. A spider mite infestation left untreated can kill your plant.
On the other hand, soil mites do not attack your plants. Instead, they feed on decaying organic matter in the soil. This promotes a healthier and fertile soil ecosystem, which provides better nutrition to your growing plant.
Spider mites are similarly less than 1/20 of an inch long, so the easiest way to determine if you have an infestation is to check if there are webs on the underside of leaves. Over time, your plant will look unhealthy as spider mites deprive the plant of nutrients. Yellow or reddish spots will appear on your plant’s leaves.
Can Soil Mites bite?
No, thankfully, soil mites cannot bite! Only two types of mites live and feed on human skin. They are the scabies mite (Sarcoptes scabiei) and the hair follicle mite (Demodex mite).
Can Soil Mites fly?
No, they cannot fly. They are eight-legged anthropods that can move very quickly but cannot fly.
Deborah is a plant enthusiast and founder of Gardening Collective.