Many gardeners are in a constant battle with the insects in their garden, and use a whole battery of shop and homemade insecticides. However many of the insect in the garden are actually beneficial to the garden and many are needed for the garden to survive.
There are three categories of these beneficial insects
Pollinators are the insects that a garden needs to survive as they aid the pollinations of flowers which is essential if fruit and some vegetables are to form, Predators eat other insects, while parasites live off the body of the host insect eventually causing death.
The predator that is most welcomed by gardeners is the ladybird (ladybug / lady beetle), these have a voracious appetite for aphids and other insects.
Another predator is the lacewing which enjoys a number of insects as a meal these include mealy bugs, aphids, spider mites, and some moths.
The tachinid fly is an example of a parasitic insect, it lays it eggs on the skin of another insect and when the larvae hatch they burrow into the body of the host insect and eat the internal organs.
Pollinators such and bees and wasps are needed in your garden if fruit, flower and vegetable production is to take place. They fly around the garden distributing pollen from one plant to another.
It is important to remember that just about all chemical pesticides cannot differentiate between good and bad insects.
Once you have purchased your beneficial insects there are some point to remember,
1 If you have used a chemical control you must wait at least three weeks before releasing your insects
2 Release the insects in the evening as they are more dormant then and hence less likely to fly off to your neighbours garden
3 water your garden before release as this will help to encourage them to stay.