Spider mites are unsympathetic worldwide pests that are like the Agent Orange of any garden and greenhouse. Once these critters stumble into your garden, your plants’ lives are tragically cut short because of the mites’ voracious appetite for plant juices. They mercilessly eat and destroy almost every type of plant life that crosses their path, including ornamental plants, crops and even trees.
Since these insects are out to gorge plant juices, your most-prized garden is likely to be their main course, instead of those unwanted weeds you pull out every day. They’re every gardener’s worse nightmare.
There are many kinds of spider mites, but watch out for the two-spotted spider mites. These little arachnids are barely visible pests. Armed with a magnifying glass, you need to inspect your plants to confirm their existence.
You can actually see that there are two dark spots on the creature’s abdomen. The spots you see are the plant juices being digested by the insects. The color of two-spotted spider mites depends on the environment. They are normally dark to pale green and, sometimes, translucent yellow. Females who try to remain alive during winter may be reddish orange in color.
Female two-spotted spider mites can lay about 200 eggs in just a ten day period. It takes only five days for the eggs to develop into a mature adult, resulting in quick population explosion. More than seven generations can sprout within the summer months. The females are born with two sets of chromosomes, which make it possible for her to produce males, even without mating. It’s life’s awesome cruelty that pests have an astonishing reproduction rate. Now, it’s time to identify their existence among your plants.
Tell-Tale Signs Your Garden Is Infested
- Stippling Patterns – Stippling is defined as engraving consisting of dots. If the leaves of your plants have brownish small dots all over, these dots are the impressions left by mites whenever they pierce the leaf to suck plant juices. Severe attacks on leaves are usually yellow or bronze in color.
- Curling Leaves – Since the mites suck out juices, the leaves eventually dry out. This is when the leaves curl inwards or outwards. These are signs that severe damage is already on its way. Once the damage reaches a certain level, the leaves will drop off because photosynthesis is stopped and carbon dioxide can’t be processed anymore. Healthy leaves are synonymous to healthy plants.
- White Webbing – You have to flip the leaves and see if there are white webs on the underside. These are silk threads that the mites use to get around the plants. In severe infestations, these webs are known to wrap up the entire plant.
Once you’re able to spot the existence of spider mites, there are three controls that can help you get rid of them: mechanical, biological and chemical controls.
Mechanical Mite Controls
Plant Isolation – There is a saying that you don’t mix rotten mangoes with the healthy ones. The same measure must be applied to infested plants. Air never remains still and changes in temperature cause the mites to move from one plant to another.
The mites are also known to have numerous means of transport. They use strands of silken threads to drop down from leaves, like Tarzan, swinging from one plant to another. These mites are eight-legged, so walking is never a problem to them. It’s a must to isolate or quarantine your infested plants to save the healthy ones.
Cold Water – Get a hose and shoot a stream of cold or ice water to knock off the mites from the plants. Mites love damp environments, but spraying them with cold water would give them major discomfort. Be careful that the stream of water is not too powerful, so as not to damage your plants. Don’t forget to spray the undersides of the leaves.
It’s best if you move the plant to another location before you spray cold water on it, because mites might climb and seek refuge on other plants. It’s a known fact that spraying cold water can also drown some of the mites, if not all of them. If you do this every day for a week, the mites will be forced to leave because of the hostile environment you create.
Shade Them Up – If possible, try keeping your plants away from arid weather and make sure they don’t get hit by the late afternoon sun. Providing the plants with some shade during very warm days will help protect the plants weakened by spider mites. You can also set a humidifier in the area where your plants are to increase the amount of water vapor in the air.
Biological Mite Controls
A familiar example of biological control is when you buy a cat to take care of mice roaming around your house. Another example is when scientists place mosquito fish in stagnant waters where wrigglers thrive. These fish are known to devour mosquito larva, effectively making a barrier to prevent mosquitoes from quickly overpopulating. The same concept can be applied to the prevention of spider mites.
You can introduce three kinds of predators in your infested garden:
- Phytoseiulus persimilis: This mite doesn’t feed on plants; instead, it feeds on two-spotted spider mites. What’s great about the use of Phytoseiulus is that these species engage in cannibalism. This means that it completely gets rid of the possibility that the cure is worse than the disease. You won’t have a garden full of mites, because in a few weeks, all the mites will disappear.
- Metaseiulus occidentalis: This is another predatory mite that’s effective in temperatures that are between 44 to 89 degrees Fahrenheit.
- Phytoseiulus longpipes: This is an African sub-variant of Phytoseiulus persimilis. This one can withstand very warm temperatures.
When considering biological controls, you can buy them from horticultural warehouses and online gardening vendors. These are usually mail-ordered. The three mites are the most commonly used predators, but there are more species of mites that eat out spider mites. Inquire at gardening centers to learn which mites best suit your garden, plantation or greenhouse.
The two-spotted spider mites (particularly the males) have the ability to mutate, allowing them to quickly adapt to environmental changes. There are some insecticides that are not lethal to these mites anymore.
They easily become immune to many insecticides, which means constantly spraying will result in killing only their enemies, not the actual mites. This causes the infestation to expand all the more. However, scientists are always ahead of pesky mites. There are still effective chemicals out there that are sure to get rid of your mite troubles.
WiltPruf: This is a chemical that’s widely available in garden supply stores. It’s formulated for use in gardens during times of drought. This chemical slows down water evaporation from leaves by covering them with a thin film.
If container directions are followed correctly, this chemical poses no harm to your plants. The two-spot is very dependent on the absence of leaf moisture to survive. The Wiltpruf coating causes the leaves to lose their moisture and eventually, the mites die out. However, this chemical cannot kill mite eggs.
UltraFine: This one is a petroleum oil spray that’s designed to kill both the mites and their eggs. When using chemicals, always remember to pay special attention to the underside of the leaves. Complete control is guaranteed when application is repeated 15-20 minutes later. Some resort to repeating the whole process after ten days to be sure that no eggs were missed.
Greenlight’s Rose Defense Spray: This is the best chemical for flowering plants. It’s made from botanical oil extracted from the seed of the Neem tree. This chemical smothers the mites but is extra gentle on plant species.
Avid or Kelthane: These are more common chemicals labeled as mitecides. Use this one every five days until there are no more signs of mite infestation. This chemical is not recommended on vegetables, herbs and crops. It contains a chemical called pyrethoids that is toxic to mites and may pose some indirect danger to humans when applied on edible plants.
Isopropyl Alcohol Mixture: This is a home-made mitecide to try if the chemicals mentioned above are not readily available. You concoct a dilution of 50% Isopropyl alcohol and water. Add a few drops of dishwashing detergent to complete the mixture. Place the solution in a spray bottle and squirt some on infested plants. Application must be done when evaporation is slower, such as during the early morning or late in the day. Repeat spraying after 15-20 minutes for best results.
Insecticidal Soaps: This is the meanest way of killing spider mites. Concocted from organic soaps like Castile, these soaps turn the spider mites into mush by dissolving them from the inside-out. The usual preparation is 2-3 drops of Castile soap per quart of water. Be sure to follow the directions carefully.
If you feel you’re not an expert in using the soap insecticide, it’s best that you buy the premixed commercial applications you can get on the Internet. Be aware that insecticidal soaps also kill any lurking insects in your garden, not just the mites.
The use of mite control systems varies according to the plants you have. If you are dealing with a flower garden, it’s best to use mitecides at once. If you’re dealing with vegetable or herbs, it’s best to use the biological controls. If you’re dealing with non-flowering ornamental plants, you don’t even have to use chemicals.
Whatever your case, be sensitive to the presence of spider mites. These mites reproduce so quickly that many farmers and gardeners around the world are often caught off guard. You could also read how to get rid of dust mites and getting rid of ear mites regarding extermination of different mites species.
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