Mites are very small arachnids, difficult to see without a magnifying glass, unless they have multiplied so much that they have become colonies. When mites invade tomato plants, they inflict small wounds on the plants that can eventually become damaged or die. The mites feed on the sap of the plant, working from the bottom of the plant upwards and on the underside of the leaves. There is no particular season in which mites are prevalent; they are active all year round. They also change color according to their life stage, which makes them even more difficult to find when they are white or blend in with the color of your plants. Keeping your tomato plants healthy and preventing mite infestation requires constant attention and watchful application of various control methods.
Steps
Part 1 of 3: Discovering the Mites
Step 1. Check your plants constantly to check for any signs of infestation
Look for signs of activity, or egg clusters. It may be useful to use a magnifying glass.
Step 2. Make sure any plants you buy aren't already infested
Check it carefully before buying it or taking it home.
Part 2 of 3: Preventing Mites
Step 1. Keep your plants far enough apart
Provide enough space so the mites can't easily move from plant to plant. A few centimeters is already quite a sufficient distance.
Step 2. Keep the plants moist (inside the greenhouse and outside)
Also, keep the humidity high (if you're using a greenhouse).
Step 3. Make sure (whenever possible) that the air in your greenhouse is circulating
Step 4. Install mosquito nets in all open windows (if applicable)
This will prevent hemiptera and the entry of insects.
Step 5. Remove any already infested plants
Eliminate or burn these plants; do not use them for composting as this will spread the disease.
Step 6. Prevent plant-to-plant migration by using sticky paper strips
Place these around your pots.
Part 3 of 3: Controlling Mite Infestations
Natural Controls
Step 1. Use natural predators such as those that feed on mites ("Fitoseide persimilis", "Neoseiulus californicus" or "Mesoseiulus longipes")
It is important that you introduce them before there is a large infestation, so that they can properly control it.
Step 2. Pick up any mites or eggs with your hands
Destroy them by crushing them or drowning them. This only works with very mild cases of infestation.
Step 3. Mist the plants using a stream of water that eliminates mites from the underside of the leaves
Be careful not to spray them on another plant.
Step 4. Spray chilli wax on the leaves (underside) to kill the mites
Repeat this application every few days. The spray will not destroy the eggs so you have to continue the application until all the hatched mites are killed.
Homemade Solutions
Step 1. Smother the mites by sprinkling 1/2 cup of flour and 1/2 cup of milk mixed with about 4 liters of water
Repeat the application every 4-5 days.
Step 2. Spray the plants with insecticidal soap to kill the mites, but be careful not to damage the plants
You can make your own insecticidal soap as follows: mix 2 tablespoons of liquid soap, 120 ml of ethyl alcohol (use the cheapest vodka you can find) and about 500-750 ml of water. Pour the resulting solution into a spray bottle. Spray on the tomato plants. You will find that it works for other insects too
Step 3. Make a garlic mixture
Put about 30g of garlic in a blender with 60-85g of onions, thirty grams of cloves, thirty grams of cayenne pepper and 1 cup of water. Stir to combine them. Add this mixture to about 4 liters of water at room temperature and spray 3 times in 5 days. This is a preventative measure, but it will also kill young mites.
Commercial Controls
Step 1. Spray the plants with a garden oil
This will suffocate the mites but will not harm the plants.
Step 2. If necessary, use any common insecticide spray
Follow the directions on the label for safety measures.
