Dragonflies are one of the most beautiful insects to visit the permaculture plot. The symmetry of their two pairs of wings, the coloration on their elongated bodies and the large eyes, combined with their elegance of movement when in the air, make for an attractive insect visitor or inhabitant of your site. But behind that aesthetically pleasing exterior lies a voracious predator. And it is this large appetite for other insects that makes dragonflies so useful to gardeners – as a method of pest control, dragonflies are actually among the most efficient. They are particularly useful if you live on a site that has problems with mosquitoes, and so can serve to make the permaculture garden a nicer place for humans to be. Dragonflies predate mosquitoes, both at the larval stage and as adults and a healthy population of dragonflies can ensure mosquitoes do not trouble you excessively even during their most active periods. They will also help to control populations of midges, and other flying bugs.
Dragonflies need access to water throughout their life cycle, so instituting a body of water on your permaculture plot is the primary means by which to attract dragonflies to your site. A pond is ideal, and doesn’t even need to be very big to attract the insects – a few feet across and with the right sort of treatment can be sufficient (although the larger the body of water – dragonfly experts suggest that 20 feet across is the ideal size – the greater the population of dragonflies it can support). You can dig a pond on your site or use a recycled container. If you are constructing a new body of water, it is a good idea to vary the depth across its diameter. Having water at various depths attracts more species of animal – including species of dragonfly – as they are able to find a niche to occupy that meets their needs. For dragonflies, it is preferable to have a body of water that is shallow at the edges and which descends to a depth of at least 2 feet in the center. This depth provides the dragonfly nymphs – the juveniles of the insect – to find refuge from potential predators at the surface. Whatever type of water body you choose to have on your permaculture plot, situate it so that it will receive some direct sunlight, particularly in the warm middle part of the day, and that it is protected from exposure to strong winds.
Exposure to sunlight and a range of depths across the diameter of the water body will also enable you to plant a dragonfly-144006_1280variety of aquatic plants, which is another way to attract dragonflies. Having a lot of plant life in your body of water is first of all a very good way to provide oxygen to the water, oxygen that animal life – such as dragonfly nymphs – require for survival. Plants also provide for other dragonfly needs. Using plants that float on the surface of the water body provides niches in which dragonflies can lay their eggs, typically on the underside of floating leaves or in the soft stems that dangle just below (a few species lay their eggs in the wet mud at the edges of water bodies). For this reason, using water lilies on your pond is a good idea if trying to attract dragonflies. Submerged plant species then provide nurseries for the young nymphs when they hatch (dwarf sagittaria, eelgrass and fanwort are popular choices) while including some aquatic plants whose stems grow above the surface if the water will give adult dragonflies places to perch. Providing a perch site is also the primary reason to ensure that your body of water has a variety of shrubs nearby. Adult dragonflies tend to hunt on the wing over the surface of a water body, and use nearby shrubs to perch on and survey the area for potential prey and potential mates. In turn, rich biodiverse vegetation around the water body provides the dragonflies with shelter from their own predators.
Dragonflies like to have flat surfaces on which to sun themselves. Being cold blooded, dragonflies bask in the sunshine to raise their body temperature and allow them to function properly to hunt. They are sensitive to temperature and so can be attracted to different colored rocks depending on the local climate conditions. In more temperate areas, for instance, they may favor dark rocks which hold and radiate heat for longer, while in hotter parts, a light color can be preferable to avoid over heating. It is a good idea when instituting your body of water to place a variety of shades of flat rocks around the pond and observe which the dragonflies favor.
As adults, dragonflies are prey primarily for birds. However, their great speed and agility on the wing means that they can often avoid capture, and so having a permaculture plot that encourages birdlife is no impediment to attracting dragonflies as well. Indeed, some of the features of attraction are the same for both types of animals, such as access to fresh water and to a variety of plant life. There is one decision that the permaculture gardener will have to make however, if attracting dragonflies is a priority: whether to stock fish in the water body. Fish of all types will feed to dragonfly eggs and juvenile nymphs, so stocking your pond with fish is likely to significantly reduce the population of dragonflies on your site. The same is true of frogs and ducks. Fortunately, if your preference is to foster an environment for fish, frogs or ducks, they will help control the insect populations of pest species, much as dragonflies will.
Attracting dragonflies to your permaculture site may mean that they predate some beneficial insects, such as lacewings, as well, but that is the pay off of creating a rich, biodiverse site. And instituting permaculture practices on your plot such as avoiding the use of chemicals and inorganic fertilizers that can run off the site into public waterways will also help to protect dragonflies that live on nearby streams and rivers.