When leaf miners attack your plants, they cause a dramatically dreadful appearance. Even worse, they can cause very serious damage.
This is why it’s very important to take steps immediately to get them under control the moment you begin to see symptoms of leaf miner predation.
In this article, we will discuss the symptoms to look for and share information on how to rid your plants of leaf miners. Read on to learn more.
What Are Leaf Miners?
There are number of different types of leaf miners, but the damage they do to plants is fairly uniform.
Adult leaf miners look like small black flies, but it is not these flies that do to your plants directly. What does damage your plants is the larva that these flies leave behind.
These larva live in the mid-tissue layers of a plants’ leaves. They are called miners because they mine the nutrients out of the leaves and create paths of emptiness in their wake.
If you do not get leaf miners under control, they will quickly skeletonize your plant leaves.
When you see their damage, swift action is imperative because once they have infested one crop, they will hang on infest crop after crop until they are reined in.
When these larva begin boring their way through the leaves of your plants, they will leave yellow, curvy lines in their wake. The insects may also leave unsightly blotches and spots on your plants’ leaves.
Below lists a few leafminer species which may cause an infestation in your garden.
Pea leaf miner (Liriomyza huidobrensis) – also called the American serpentine leafminer. The larvae infest on the leaves and stems of peas. It may also affect other range of vegetables.
Boxwood leafminer – This type of leafminer feeds on the upper and lower parts of a plant’s foliage. Signs of boxwood leafminer infestation include leaves turning yellow and drying making its victim look extremely unhealthy.
Beet leafminer – The adult fly resembles a regular housefly. The maggots of these insects tunnels through the leaves of Swiss chard, spinach beets and other related plants.
Citrus leaf miner – Small, light-colored moths that infest citrus trees such as lemons, limes, oranges, grapefruits and more. Although it is native to Asia, it currently causes infestation in Southern California gardens.
Spinach leafminers – They usually appear during spring and chooses young robins and daffodils as its favorite host plants. They lay eggs on the leaf surface and underside of a leaf where it pupate and spend most of its life cycle.
Tomato leafminer (tuta absoluta) – is a known serious pest found in tomato plants. The larvae feeds voraciously on crops and mines in stalks.
How Can Leaf Miners Be Controlled?
For a quick leafminer control fix, before they make their initial appearance, you can give your plants a good spraying with neem a general pesticide. You have to time this perfectly so that the pesticide kills the larva and the adult flies. If you spray too early, your poison will not injure either the eggs or the adult flies. Remember that the leaf miner larva are your target.
To get rid of them with pesticide, you’ll need to do a little testing. Early in the spring, locate some leaves in your garden that are infested with leaf miners. Place these into a sealed plastic bag and check the bag every day.
When you see that the leaf miner larva have become adults (little black flies) you’ll know that it is time to start spraying your plants. Begin immediately, and spray your plants every day for seven days.
What Kind of Pesticide Should You Use?
Look for a type of spray that is pacifically designed to kill leafminers. Alternately, you may seek more biological control or natural solutions such as Neem oil. This is an insecticidal oil that is less harmful to the general environment than commercial pesticides.
Be advised that you will need to apply Neem oil very uniformly, more frequently and for an extended period of time in order to have any results at all. Neem oil disrupts the lifecycle of the leaf miner and prevents the larvae from becoming adults. Over time, this will help you get your leaf miner problem under control.
Is Spraying Your Best Option?
While spraying is the quickest option if you are suddenly surprised by a leaf miner invasion, it is not really the best option the reason for this is that leaf miners live inside of plant leaves, so they may not even be affected by pesticide or organic insecticidal spray unless you are extremely diligent and persistent with your treatments.
It’s important to understand that when you spray for leaf miners, you will also end up killing off a great deal of friendly fauna in your garden, and you may have little or no effect on your leaf miners. In the long run, this is counterproductive because killing off friendly fauna means killing off natural leaf miner predators.
Although it takes a bit more time, it is far wiser to enlist the aid of natural predators of leaf miners. Leaf miner parasitic wasps (Diglyphus isaea) are the main natural enemy of these ubiquitous garden pests.
These tiny wasps prey on leaf miners by laying eggs in their larvae. When the eggs hatch, the wasp larvae feed on the leaf miner larvae. You can purchase Leaf miner parasite wasps as adults from online organic garden suppliers.
Related Reading: Using Giant Ichneumon Wasp Larvae To Control Garden Pests Naturally
In addition to creating a strong defense against leaf miners, you should also practice passive resistance by making your garden less appealing to them in the first place. Be sure to get rid of any plants in your yard that tend to harbor leaf miners.
Some examples of plants that attract these pests include green leafy plantain and also chickweed. These are common hosts for leaf miners, and having them around can really increase the risk that your spinach, chard and other leafy green veggies will be invaded by leaf miners.
Patience Pays Off
When your garden is being visibly consumed by ravenous pests it can be very tempting to mount an aggressive and poisonous offense against them. While spraying can be effective in the short term, it may end up causing more problems with the passage of time.
Protecting your garden from potentially hazardous chemicals also protects you, your family and the environment. Understand that when you are using natural, organic alternatives you must be very diligent, patient and persistent. With natural solutions, you should strive to attain a harmonious balance in your garden. This natural balance will help protect your garden against leaf miners and many other forms of pest.