Predatory insects are one of the best natural methods of pest control for the garden. They are the only things meticulous enough to seek out and destroy the pests that are living in your garden individually. The goal of using predatory insects is not to wipe out a pest invasion, rather they reach a balance between the pest and the predator. This keeps the damage to a minimum and avoids the use of nasty chemicals or pesticides.
Bug Balance in Nature
In nature, there is a balance between predator and prey which ensures the survival of both species. If the predator species outgrew the prey they feed on and ate them all, there would be no food left for them to eat and they would end up dying as well. If the prey grew out of control and was not kept in check by the predators that eat them, they too would grow into large colonies and likely destroy their own food source to the point of self-oblivion.
This is why a balance is always found in nature. When prey grows in number, predators have more food and begin to thrive. As they thrive and grow in number, they eat more prey and less food becomes available once again. With less food available, more die off. This is a constant cycle between predator and prey that keeps their numbers in check and ensures the survival of the species.
This is why using predatory insects in your garden will not result in a complete obliteration of the pest. Rather, it will keep them in balance, and prevent their numbers from growing out of balance.
With indoor growing, there is no natural balance between predator and prey. This is why a small spider mite or thrips infestation, can quickly grow out of control and destroy your entire crop. Many growers choose to use predatory insects to bring a natural balance to the grow room and keep pest species at bay.
What are the most common predatory insects?
1. Minute Pirate Bugs
Minute pirate bugs are one of the most common insects in the wild, and they can eat a huge variety of insects or insect eggs. They are also easy to cultivate in the garden.
2. Thrips predators
Thrips predator is actually a mite, which is very similar to spider mites. Although spider mites are in fact significant garden pests, predatory mites are the complete opposite. They are very fast moving, and do not feed on plants. Instead, they run around the surface of the leaves and attack the egg and larval stages of thrips. They are small enough to reach the thrip eggs that are safely hidden beneath the surface of the leaf tissue and are fast enough to catch these quick-moving insects.
3. Trichogramma Wasps:
There are many species of parasitic wasp, and Trichogramma species are simply one that preys on some of the common garden pests we endure as gardeners. They are incredibly small, and unlike what you normally might think of as a wasp, they do not sting.
They live by laying their eggs inside the eggs of other species, which consume all of the energy from that egg and hatch from it instead of the original species very quickly. These wasps, in particular, are perfect for controlling over 200 varieties of caterpillars, and a wide variety of other insect eggs.
4. Beneficial nematodes
Nematodes are microscopic creatures that naturally live in the soil. By introducing them into your coco, or soil grow, you can protect your crop from the larval stage of insects like thrips that spend this stage of their life in the soil around the roots of the plants.
Nematodes are brutal parasites to larval or pupal stage insects. They enter the host insect's body and release a toxic dose of bacteria to kill it. They then feed on the decaying body of the insect.
Ladybugs or “ladybirds” are some of the most iconic insect species around. Their humble nature and attractive outfit make them one of the most popular insects to keep in the garden. Their benefits go much further than this, however. Ladybugs have an insatiable appetite for all kinds of garden pests, namely aphids, and spider mites. One ladybug can consume over 50 aphids a day.
Ladybugs are easy to cultivate, just ensure a water source is handy and avoid spraying any pesticides in your garden while they are present.
A note on using beneficial insects in your garden
Try to avoid using pesticides on a garden you have introduced predator insect into. Pesticides are nonspecific and will kill all insects, including your predatory insects. If you must use a spray pesticide, keep in mind that this WILL kill your beneficial insects as well.
For larger predators such as ladybugs or pirate bugs, it may be possible to go through your crop and collect as many as possible before spraying, to then reintroduce after the application has been finished.