Spider mites, while members of the arachnid family, have little to do with spiders. Spider mites are tiny pests that infest your plants, eat the leaves, and suck the life out of your garden.
Their reproductive habits are enthusiastic, meaning a small number of mites can explode into a full-blown infestation in under a month, and also means that they develop quick immunities to the chemicals in pesticides.
They offer virtually nothing of benefit to your garden and leave destruction in their wake. In short, they’re bad news. So how do you get rid of spider mites?
There are ways to deal with them. In this article, you’re going to discover how to recognize spider mite infestations, things you can do to prevent them, and how to deal with an infestation.
What Do Spider Mites Look Like?
Common Homes for Spider Mites
- Potted Begonias
- Broad-Leafed Weeds
- Frangipani
- Bananas
- Beans
- Fruit Trees
- Strawberries
- Mint
- Miniature Roses
- Indoor Houseplants
Spider mites are tough to see because they’re tiny. At about 1/20th of an inch in size, they’re invisible to the naked eye unless you’re looking for them, and even then you’ll probably need a magnifying glass. They have oval-shaped bodies and tend to have a pale or reddish-brown color. You usually find them in hot, dry conditions (above 85 degrees Fahrenheit [29.44 C] and with less than 60% humidity) and they prefer certain types of plants over others.
Lacking a magnifying glass, one way to check to see if you have spider mites is by holding a piece of white paper under the plant and carefully shaking the leaves. If you have an infestation, you’ll notice black specks on the paper that resemble pepper.
Evidence of Spider Mites
Chances are, you’ll see the proof of spider mites before you notice the bugs themselves. They’re known as web-spinning mites because you’ll see delicate, milky white, silky webbing on your plants, particularly on the undersides of the leaves. You may also notice small white, yellow, or brown bite-marks on the leaves. Spider mites eat the chlorophyll in leaves, so you’ll see evidence where they’ve been feasting.
Once you’ve recognized a spider mite infestation, you’re racing the clock. A single female is capable of laying 300 eggs in a few short weeks, meaning their population can explode out of control in a short period.
If you think you have an infestation, check all of the plants in your home, again looking for bite marks in the leaves and webbing. Once you’ve identified which plants are infected, you can turn your attention toward treating them.
How to Get Rid of Spider Mites
Preventing Spider Mites
The easiest way to treat a spider mite infestation is to keep it from occurring in the first place. Luckily, the preventative steps are relatively easy. Here’s how to prevent spider mites on your houseplants.
Water your plants on a regular basis. If you’re taking good care of your plants, you’re probably already watering them regularly. Spider mites prefer dry areas, so a well-watered plant is going to be an effective deterrent. Additionally, spider mites like warm environments, so using cold water instead of hot or lukewarm water is going to provide an additional barrier against an infestation.
On top of watering your plants, dust them regularly. There are a couple of ways you can take care of dust on your plants, depending on the type and size of your plants.
Plant Care to Prevent Spider Mites
- Clean Smaller or Fragile Plants with a Cloth
- Spray Stronger and More Resilient Plants With a Hose
- Clean each leaf with a cloth. Using a damp cloth is better for smaller or fragile plants. Wipe down each leaf, taking care to clean the tops of the leaves as well as the undersides. Spider mites will often make webs on the undersides of leaves, because they prefer to avoid direct sunlight.
- Spray the plants. Using a sprayer is better for larger and more durable plants. Do this by taking them outside and using a garden hose, or by placing them in a sink or bathtub.
Create a humid environment for your plants. Spider mites prefer dry areas so the wetter, the better. Spray water onto the plants each day. If your plants are small and sit on plates or platters, put water onto the plate to increase humidity.
Keep your plants shaded whenever possible. Plants need sunlight, but consider closing your curtains during the hottest time. If you’re unable to shade your plants, consider investing in a humidifier and putting it next to them to maintain a humid environment.
How to Kill Spider Mites
The first step toward spider mite control is to isolate the infested plants. Start by stripping infected leaves from the plant and either putting them in a sealed bag and throwing them away or burning them. Consider getting rid of the plant altogether. Spider mites can ride on air currents from one plant to another, so isolate the plants and put them close together to reduce air flow. Water the plants as often as possible to create a moisture-rich environment and if possible, place a humidifier nearby. You want to create as much humidity as possible.
If you cannot isolate the plants, you can still treat them. Use rubbing alcohol to make a 1:1 mixture of alcohol and water and spray the leaves. The rubbing alcohol will destroy the mites’ exoskeleton and create an unsuitable environment for them. It also evaporates quickly, meaning the plant will be okay after the treatment.
Types of Predatory Mites
- Phytoseiulus persimilis
- Phyoseiulus longpipes
- Metaseiulus occidentalis
Sometimes, it’s better to fight fire with fire. Introduce certain types of mites to your plants, and they’ll wipe out the spider mites without hurting your leaves. Do a Google search or take a trip to your local nursery and ask about predatory mites.
The process is easy and straightforward. The predatory mites will start by eating the spider mites. Once the spider mites are gone, they’ll cannibalize each other and wipe themselves out, making them useful and self-contained biological controls.
Natural Remedies for Spider Mites
A frequent error gardeners make is that they attempt to use pesticides to treat spider mite infestations. Avoid using pesticides. Spider mites develop quick immunities, so what you’ll end up doing is killing the insects that prey on the spider mites.
In short, chemical pesticides encourage spider mite infestations. So what’s the best way to kill spider mites?
To treat spider mites naturally, try the following techniques.
Rosemary
On its own, rosemary oil is effective against spider mites because it attacks their nervous system. Blend rosemary essential oil with water, or buy a rosemary-based pesticide. Rosemary is known for deterring spider mites, and it is not harmful to the plant or beneficial predatory insects.
One of the best aspects of rosemary oil is that it works in tandem with biological controls. Rosemary will deter spider mites, but it has no effect on the predatory mite Phytoseiulus persimilis. As with many essential oils, rosemary oil is also an excellent remedy to repel and keep spiders away.
If you’re having trouble with multiple types of insects on top of spider mites (such as aphids, ants, and ticks), mix a solution rosemary oil, peppermint, thyme, and clove for an all-purpose, all-natural insecticide. Again, predatory mites are resilient to natural oils, meaning you can apply the solution without hurting them.
Neem Oil Spray Recipe
- Neem Oil (2 Tbsp)
- Dishwashing Detergent (1/3 Tsp)
- Warm Water (1 Quart)
Neem Oil
Neem oil is excellent at deterring pests like spider mites. As long as you use neem oil correctly, you can get safe, natural results. Ideally, spray the plants in the evening so that they will stay dark for at least five hours. Neem oil can be sprayed every three days for three weeks until the spider mites are gone. If you’re making the solution at home, mix neem oil into water. You can also buy pre-made neem oil solutions at most gardening stores.
Soap
Spider Mite Soap Recipe
- Non-Detergent, non-degreaser Soap (3 Tbsp)
- Warm Water
- Cold Water
- A Tablespoon
- 1-Gallon Jar
- Spray Bottle
- Timer
Soap is a mild, effective means of taking care of spider mites. Soap covers spider mites and suffocates them.
Start by adding liquid dish soap into a 1-gallon jar. You’ll want to go for a mild soap, avoiding detergents and anything with degreaser as an ingredient. Fill up the rest using warm water. Shake the jar thoroughly until the solution is well blended with the water and pour into a spray bottle.
You might consider testing the solution first, to make sure that the soap isn’t going to hurt the plant, by applying the solution to a small section before committing to treating the plant in its entirety.
Apply the solution directly to the mite infestations. You want to saturate the mites thoroughly, and the leaves should be well-doused. Take care to be detailed, spraying each leaf individually instead of the entire plant. Avoid spraying the strong parts of the plant.
Allow the solution to set for two to three hours, which will give the spider mites time to die off. At the end of the three hours, clean the soap from the plants using cold water.
Throw away whatever soap solution remains. Instead of keeping it, make a new batch each time you want to spray for mites. Apply the soap solution about once a week until the infestation is gone.
Diatomaceous Earth
Characteristics of Good DE for Plants
- Meets Food Codex Standards
- < .1% Crystalline Silica
Diatomaceous Earth (DE) is the fossilized remains of tiny ocean plants called diatoms. DE is dust that looks like flour, and it’s extremely dangerous to spider mites because it desiccates them until they die. In other words, DE has a property that causes it to suck up liquids and fluids. It eats away at the spider mites’ cuticle’s outer layer, making it impossible for spider mites to maintain the fluid levels necessary to keep them alive. They dry up and perish.
While searching for DE to use, keep an eye out for a couple of things. You’ll want a DE that meets Food Codex Standards (which means it’s safe for you to handle) and has less than .01% crystalline silica.
Avoid using pool grade DE, because it’s loaded with crystalline silica and is dangerous to breathe.
DE isn’t an end-all-to-be-all for infestations, and you’ll probably want to incorporate other tactics on top of it, but by dusting your plants with DE consistently, you help to prevent the spider mites from infesting in the first place.
Pyrethrum
Pyrethrum, made from the pyrethrum daisy, is an organic pesticide and contact killer. It’s a nerve agent, meaning you spray it on the mites and they first become paralyzed, before dying.
Will it work? Yes.
The trouble is that, much like with pesticides, it’s toxic to virtually all insects. Unlike with pesticides, you will kill the spider mites, but you’ll also kill beneficial insects that pollinate your plants and otherwise keep them healthy.
How the Mite-y Have Fallen
Spider mites can be tough to get rid of, but luckily there are plenty of ways you can handle them. If you’re dealing with an infestation, keep at them. Try different techniques and figure out what works. When you finally get rid of them, use the suggestions above to keep them away for good.
In this article, you learned how to get rid of (or kill) spider mites and some natural remedies that will help you do so. Have you noticed spider mite webbing on a friend’s plants? Is a family member of yours dealing with an infestation and feeling overwhelmed? Use the buttons below to share to Facebook, Pinterest, and Twitter.
