Controlling Indoor Pests – Leaf Miners
If you’re looking for a true challenge when it comes to an indoor pest, look no further than the leaf miner. The leaf miner is more of a threat to an indoor gardener using a greenhouse, but leaf miners have been known to develop in any indoor garden when conditions are right.
Although there are standard ways to deal with most pests, even identifying these pests can be challenge. The adult leaf miner looks exactly like small fly. Without an expertise in entomology, you probably will not be able to spot them, even if you study them on sticky yellow monitoring tape.
The problem with leaf miner is that they do exactly what the name implies — mine the leaf of your plant. Basically, the adult leaf miner lays an egg on the leaf of the plant and it hatches a larva. In turn, the small larva tunnels between the upper and lower surfaces of the leaf and goes to work. And, of course, because it is between the layers of the leaf, it is protected form any sprays you might want to use.
One of simplest ways to protect from an outbreak of leaf miners is to have concrete floors. If the larvae fall into soil, they will pupate and become leaf miners, finding their way onto your plant. But if they fall onto a hard surface, they are instantly killed. Thus, leaf miners aren’t the most common threat to an indoor garden. That doesn’t mean, however, that you are completely protected if you are running an indoor garden setup.It is very easy for leaf miners to invade your current setup if you bring in anything from an outdoor setting. Plants that are already infected with leaf miners are one of the perfect ways to introduce them into your setup. Because they are so hard to detect, you might think you are bringing in a healthy cutting, but that can be the beginning of the end. Like every species of pest we’ve discussed over the last year, it is constant vigilance that will rule the day.
Regarding their lifecycle, it takes about three weeks for leaf miners to mature from egg to adult, though they do have a hard time properly reaching maturation in an indoor garden setting. They are more common in the southern states of the U.S. than in the northern states.
Like most critters, leaf miners do have some preferences. They enjoy the leaves of vegetables such as tomatoes, peppers, spinach, squash, and pumpkin. If you do have an infestation, the best way to detect it is to study the leaves. Long, slender, winding white tunnels in the leaves of the plants indicate leaf miner damage.
To control an outbreak that has reached the point of plant damage it is best to simply pick the infected leaves off the plant. Because they are protected from all types of chemical sprays when this point is reached it will be your most effective option. If you do not want to pick apart you plant, you can try natural predation.
Biologically, leaf miners are best controlled by parasitic wasps. There are a couple of different types of wasps that you can use, but your indoor retailer might recommend one over another. The wasps work by laying eggs near the leaf miner larvae. The wasp larvae hatch and feed on the fluid of the leaf miner larvae.
In any well-planned indoor garden the leaf miner should not pose a significant threat. If you are using a greenhouse, however, make sure you are always checking for the possibility of infestation. Remember, it’s always better to prevent than to react.