Spider mites are small pests that damage gardens and landscaping. They consume fruit trees, ornamental houseplants, vegetables, cannabis, and other common plants. If left unchecked, spider mites can reproduce rapidly and kill cannabis plants. Fortunately, you can use simple techniques to protect your cannabis plants from these destructive pests. Here’s what you should know about spider mite characteristics, risks, and removal strategies.
Spider mites are cannabis pests that are part of the mite family. They’re related to ticks and spiders. These critters have two body segments, eight legs and come in different colors based on age and species, including green, orange, red, and yellow. Spider mite populations flourish in warm, dry environments, making them one of the most prevalent insect concerns farmers encounter while growing cannabis indoors and in greenhouses. The red species are usually known as red spiders.
In addition, some change colors throughout the year, while others are translucent. All spider mites are very small, 1/60 to 1/25 inch, and are typically identified by the silky webbing they spin on cannabis plants and the general damage they cause to foliage. The most common species, adult two-spotted spider mites, have eight legs roughly the size of a grain of sand or a pencil period.
Spider mite infestations can cause stunted growth and reduced yield in weed plants. Webbing is a common indicator of spider mite infestation on cannabis plants. To identify spider mites, look for these common signs:
Spider mites cause weed harm by puncturing the leaf cells and sucking all the nutrients. The weaker leaves begin to harm the entire plant. The plants’ growth slows as they try to share their nutrients with the mites. The crop droops as the buds struggle to reach their full size and maturity. If not addressed, the plant may perish from extended weakness. Ultimately, spider mite infestations can lead to stunted growth and reduced yield in cannabis plants. In addition, spider mites can develop resistance to pesticides, making control challenging.
Prevention is the initial step in treating a spider mite infestation. Your grow room environment is key. Maintain correct environmental conditions such as temperature, humidity, and ventilation. Here are some tips to make spider mites prevention second nature:
Here are some effective non-chemical ways to eliminate spider mites indoors and out.
It may appear extreme, but you want to eliminate any chance that a possibly mite-infested plant can harm the rest of your foliage. Experts recommend separating indoor plants from the rest for several weeks and checking for signs of spider mites and other pests before introducing new purchases to the rest of your collection. In addition, ensure your cannabis plants are well-watered and fertilized. Excess nitrogen makes your weed plants more vulnerable to spider mites. Healthy cannabis plants are more resistant to pests and illnesses, but weaker or stressed plants are more vulnerable to issues.
Pesticides can be an efficient way to manage spider mites, but they have both advantages and disadvantages.
Pros of using pesticides for spider mites
Cons of using pesticides for spider mites
Boosting the natural defenses of your cannabis plant involves a combination of good gardening practices, strategic stress application, and maintaining a healthy growing environment. Some of the successful ways to do so, include:
High humidity and dusty conditions can favor spider mite infestations. Therefore, proper ventilation plays a crucial role in preventing spider mite infestations. Here’s how proper ventilation helps:
You can use two main strategies: plant resistance and placement to protect your plants from these spider mites. Plant resistance means choosing cannabis strains that have natural or bred-in resistance to spider mites, such as some Indica or Ruderalis (Gorilla Glue #4 Auto and Zkittlez Auto) varieties. Plant placement means arranging your cannabis plants to make them less attractive or accessible to spider mites, such as by intercropping them with other plants that repel or distract them or rotating them with different crops to break the mite life cycle. These methods can help you prevent spider mite infestations and save your harvest.
Spider mites flourish in dry environments with temperatures about 30 °C. Spider mites can become interior pests throughout the winter because of the dry and heated temperatures. You should increase room humidity, especially in the winter when the air in the house is dry. Use a room humidifier or sprinkle plants with a spray bottle regularly. You can also grow your cannabis plants in trays filled with stones and a tiny bit of water. Don’t let the pot’s bottom sit in standing water. In addition, when bringing potted plants into the home for the winter, be especially cautious. Examine the cannabis plants for spider mites and other pests.
Regularly inspect your cannabis plants for any indicators of spider mites or other pests. Early detection enables rapid response action and prevents extensive infestation. The spider mites can multiply and spread quickly, making it difficult to control an infestation once it becomes established.
It may come as a surprise, but certain helpful insects can help minimize a spider mite infestation. Predatory mites like Phytoseiulus persimilis and gall midges like Feltiella acarisuga will help keep the pests at bay. Natural predators like ladybugs (commercially available) can help control spider mite populations. Predatory mites make sense to utilize mostly in greenhouses or indoors, where spider mites eventually inflict the greatest harm.
Beneficial insects will stay in a confined space soon. Thus, it is important to note that, although labeled as “predatory,” the small helpers are not hazardous to people. Constructing a habitat in the garden or field where predatory mites will organically multiply makes sense. Pesticides should not be used to treat a spider mite infestation with helpful insects since they may harm the beneficial organisms.
Spider mites can be introduced to cannabis plants through contaminated soil, equipment, or nearby infested plants. Here are some cleaning and disinfecting techniques to prevent their spread:
Remember, treating plants thoroughly and regularly for several weeks is important to eradicate spider mites completely. If only a few cannabis leaves are damaged, use a disinfected cutting tool to eliminate them, then treat the plant. If the infestation is heavy and most weed leaves are damaged, it might be time to discard the cannabis plant.
Prune any spider mite-infested leaves and stems, placing the cuttings in a plastic bag and disposing of them in the garbage rather than your compost (eggs can stay latent until the right hatching conditions occurs). If the entire weed plant has mites, or its health appears too far gone to recover, consider plucking it to prevent the infection from spreading to others.
Understanding how to eliminate spider mites on indoor weed plants is simple since you have greater control over the atmosphere. To efficiently eradicate them, lower the temperature, enhance humidity, and promote air circulation.
If you have good eyesight, you can see individual spider mites on the cannabis leaves as you tend your plants. However, because they are so small and like to reside on the undersides of leaves, you will most likely have to put in some effort to capture them before they cause severe harm. Noticing them before populations increase can simplify your life as a gardener because it can be difficult to obtain (or recover) total control after they’ve invaded a plant. Cannabis growers can also do the following practices:
If spider mites are found on buds during harvest, it may be too late to save them. Mites prevent the buds from maturing correctly, causing them to remain small. As a result, it may impact the quality and potency. If the buds are not severely damaged, gently water them down or add mite predators. You may also spray a DIY spider mite killer that won’t interfere with the taste.
Ed Rushford’s impact on cannabis growing is undeniable. Though he tends to focus primarily on 2 areas, plant training techniques and dealing with disease, pests, and other problems, he has offered many insights into how cannabis plants live and grow. That’s not to say that Ed is unfamiliar with the complete life cycle of cannabis, from seed to harvest, but he uses his widespread knowledge to hone in on the minutia and niche areas of growing cannabis. Ed’s goal is to spread knowledge and allow for everyone to become better growers. About this Author