Spider mites are a common garden pest that can quickly infest and damage outdoor plants. Getting rid of spider mites requires diligence and patience, but there are organic and chemical treatment options that can help eliminate an infestation. Here is a comprehensive guide on how to identify, prevent, and get rid of spider mites on outdoor plants.
What Are Spider Mites?
Spider mites are tiny arachnids, distantly related to spiders. There are many different species, but the two most common on outdoor plants are the two-spotted spider mite and the spruce spider mite.
Adult spider mites are only about 1/50 of an inch long. They are usually pale yellow or greenish with two dark spots on their backs. Spider mites spin fine silken webs on plant leaves, where they lay their eggs and feed on sap.
An infestation often starts when spider mites blow in on the wind from other plants. Hot, dry conditions provide ideal breeding ground for rapidly multiplying populations.
Signs of Spider Mites on Plants
Detecting spider mites early is key to effective treatment. Watch for these signs:
- Fine webbing on leaves and stems
- Speckling or yellowing on leaves
- Drooping or wilting leaves
- Slowed growth
- Premature leaf drop
Check the undersides of leaves closely using a magnifying glass. Spider mites often congregate along the veins. Tap a leaf over white paper to dislodge mites for easier viewing.
How to Get Rid of Spider Mites Naturally
For mild infestations, non-chemical treatments can be effective for getting rid of spider mites. Try these organic solutions:
Remove Weeds
Weeds around the yard harbor spider mites. Pull them up and dispose of them away from planting beds.
Hose Off Plants
A strong stream of water can blast away spider mites and their webs. Focus the spray on the undersides of leaves. Repeat every few days for two weeks.
Apply Insecticidal Soap
Insecticidal soaps based on potassium salts of fatty acids will kill spider mites on contact. Spray plants, including the undersides of leaves, every 5-7 days for a few weeks.
Use Neem Oil
Extracted from the neem tree, this natural oil coats pests and disrupts their feeding and reproduction. Mix according to label directions and spray on affected plants.
Release Predatory Insects
Ladybugs, green lacewings, and predatory mites will feed on spider mites. Obtain them from garden supply stores and release near infested plants.
Apply Horticultural Oil
Dormant oil or other horticultural oils smother spider mites when applied to affected plants during cool weather. Coat plants thoroughly.
Chemical Spider Mite Treatments
For severe infestations, pesticide sprays are effective at wiping out mites. Some options include:
- Miticides – Pesticides targeted specifically at mites, such as abamectin.
- Insecticide/Miticide Mix – Broad-spectrum chemicals like carbaryl kill mites in addition to other pests.
- Sulfur – A natural mineral spray that kills mites through contact. Avoid applying sulfur during hot weather.
Carefully follow all label directions when using chemical miticides or other pesticide sprays. Repeat applications may be needed for full control. Consider discarding heavily infested plants to eliminate the mites.
Spider Mite Prevention Tips
Preventing spider mites from ever gaining a foothold is the best defense. Try these gardening practices:
- Promote air circulation around plants through proper spacing and pruning.
- Avoid excess nitrogen fertilizer which produces succulent, vulnerable growth.
- Wash off plants with a strong spray monthly to keep mite populations in check.
- Introduce predatory mites which feed on spider mites but not plants.
- Use insecticidal soap or horticultural oil early in the season before mites multiply.
- Check new plants thoroughly for webbing before bringing home from nurseries.
- Control dust which can harbor windborne mites through mulching and light watering.
Frequently Asked Questions About Spider Mites
How do you know if you have spider mites?
Look for fine webbing and speckling on plant leaves. Check the undersides of leaves closely for tiny mites congregating near veins. Tap leaves to dislodge mites for easier viewing.
What is the best natural way to get rid of spider mites?
Insecticidal soap, neem oil, and horticultural oils are highly effective organic spider mite treatments. Predatory insects like ladybugs will also feed on spider mites.
When should you spray for spider mites?
Treat spider mites early before populations explode. Natural sprays can be used anytime when mites are detected. For chemical miticides, optimal timing is just before leaf buds open in spring.
How do you permanently get rid of spider mites?
Completely wiping out mites is difficult. The best strategy is prevention through proper plant spacing, pruning, fertilizing, and frequent washing of plants. Discard heavily infested plants if mites persist.
What chemical kills red spider mites?
Miticides containing chemicals like abamectin, bifenazate, or fenpyroximate work well to control two-spotted red spider mites. Insecticides with pyrethroids can also kill mites. Always follow label directions.
Can spider mites kill plants?
Yes, uncontrolled spider mite infestations can kill plants. The mites’ feeding damages leaves and sucks away plant juices. Webbing also prevents proper photosynthesis. Their toxic saliva can also cause disfigured growth.
Conclusion
Spider mites are a common and destructive garden pest. Catching infestations early and taking quick action increases the chances of eliminating them before major plant damage occurs. Combining preventative cultural practices with organic sprays and chemical miticides as needed can help get rid of spider mites and keep them away from your outdoor plants.