How to Control Spider Mites Organically

Have you started seeing tiny dots on the leaves that are orange, yellow, or white?  Have you noticed light webbing over the leaves or buds?  

No, you don’t have a nutrient problem or an infestation of spiders.  It’s more than likely an infestation of tiny little bugs called spider mites.  

These bugs while small can create havoc in your growroom.  The time is now to eliminate these pests from causing issues in your crop.

What are Spider Mites?

Spider mites are tiny little bugs that fall into the mite family and are related to ticks and spiders.  They are rather tiny with females being about 1/64th of an inch and males are 1/50th of an inch.  It’s not surprising that these are called spider mites because like their relatives they can create a webbing.  This silk webbing is very fine, and can ruin your crops.   

For growers, they are a common pest and are often very hard to get rid of because you may not notice that you have them in your growroom until it’s a serious infestation.  They have these tiny little mouths that are very sharp which they use to pierce the plant cells.  This allows them to suck out the contents of the leaf.  These leaves will often turn yellow or brown, and will die off earlier than they should.  This may not seem too concerning except for the fact that a bad infestation of these mites can actually kill your plants in just one night.

Spider mites can be a huge problem as just one female spider mite can be the mother to about a million mites in less than four weeks.  This rapid rate of reproduction is just one way that makes it hard to get rid of them.  Another reason why these are annoying pests to deal with is that you may think that you’ve gotten rid of them, and then they pop up again days or weeks later.

While spider mites are often more common in growing situations where soil is used, they can still be found in hydroponic gardening set-ups.  Certain varieties of spider mites really love specific plants, and there are some that have a resistance to insecticides.

Life Cycle of the Spider Mite

As females can produce such a huge amount of eggs, it’s important to understand the life cycle of the spider mite to help you in your battle.  Thinking you eradicated them to have a very small population survive means that they’ll make a comeback.

It takes a few days to a week for the egg to hatch on the host plant.  These larvae will eat for a few days, and then, molt into a nymph.  This nymph will then feed for a few days, and then molt into the second nymph stage.  They will repeat the pattern of eating for a few days before resting to then molt into an adult.  Depending on the variety of spider mite, it can take days or weeks for them to go through this whole cycle.

This cycle means that there are several stages of juvenile spider mites that need to be completely eradicated.  You’ll want to continue treating your growroom long after you believe the mites are gone to ensure that every stage of the lifecycle is dead.

Prevention and Early Detection

As spider mites are so small, they can often go undetected until they are a huge problem.  You can detect these pests by doing a very thorough inspection of the leaves.  They are often found on the underneath side but can be on either side.  You can use a hand lens to really inspect the leaves carefully.

Inspect your current crop often to ensure that it’s clear, and whenever you go to bring in new plants into your grow set-up, inspect them before bringing them in.  You don’t want to introduce them into your growroom by accident.

Environmental Treatments

One of the first things that you should address when you have discovered a problem is the environment.  Spider mites enjoy an environment that is calm and hot.  You’ll want to adjust the heat, and have fans or blowers circulating the air around the leaves and the growing medium.  

These won’t kill off the spider mites, but it can make it harder for them to lay eggs.  Plus, the added air circulation can help the treatment you choose to use dry quicker.

Organic Treatments

Botanical Oils (Insecticidal Oils)

Plant-based botanical oils are very effective when spider mites are present providing quick knock-down, contact control that smothers mites by clogging their spiracles, or breathing pores, and breaking down their outer cellular membrane.

Although some have repellent properties, in order for them to work properly they must come into direct contact with spider mites.

There are a number of botanical oils formulated around plant extracts such as cottonseed, garlic, clove, cinnamon and others, but rosemary, peppermint, and soybean oil have shown to provide the most consistent miticide activity in agricultural crop trials.

That’s because not only do they provide a solid, lethal, contact mode of action, but the rosemary and peppermint oils, primarily, consist of complex terpenes and terpenoids that are very insecticidal in nature.

These oils also function as neurotransmitter disruptors which confuses and repels insects from feeding on your plants.

That’s why we formulated our product, Mantis EC Botanical Insecticide/Miticide, with these key active ingredients.

CLICK HERE for technical information, trial data, and testimonials on Mantis EC.

Neem Oil

Our organic friend, neem oil, is also effective on spider mites.  One issue to keep in mind when using neem oil is that it can impact the smell and taste of buds when you use it on plants that are flowering.

Click Here to get a FREE bottle of Mantis Cold-Pressed Neem Oil!

Diatomaceous Earth

When using soil as your growing medium, you can use diatomaceous earth to help with getting rid of the spider mites.  

This won’t eliminate your infestation, but it can be one more step in reducing it.

Click Here to try Mantis Diatomaceous Earth!

Beneficial Insects

Growing outdoors means that you can release beneficial insects to help reduce your spider mite population.  Ladybugs are great for these pests, but are another measure that probably won’t eliminate them completely on their own.

Click Here for more info on beneficial insects and biological control methods.

Steps to Eliminating Your Spider Mite Problem

1. Kill as many spider mites as you can with environmental treatments and one of the spray products.
2. Repeat your first method of killing them as well as using another method a few days later.
3. Repeat these steps until you believe that the population of spider mites is gone.
4. Repeat these steps once more even after you think they are gone to ensure that they won’t show back up later thanks to a few missed eggs.
5. Put a prevention and early detection plan in place.

Spider mites can be a huge issue.  It can often be enough for a grower to want to torch their plants and just start over again, but you don’t have to go that drastic.  Using these organic methods can help you to get rid of the infestation.  Just make sure that you don’t give up on it too soon and allow them to make a comeback.   

P.S. Having trouble controlling insect pests organically?  Click here to download a list of the the best organic pesticides that work FAST and are used by professional crop advisers.