Ten 'Beneficial Bugs' for the Sustainable Garden
As strange as it may seem, many kinds of bugs are a gardener's natural allies in the war against, well...bugs. In your effort to minimize the use of chemicals in your garden, consider the benefits of welcoming the presence of certain insects to help keep the impact of their peskier counterparts in check. The following list is general -- not geared toward any specific geographic region -- so find out which bugs thrive in your specific climate when planning to rely on insects as a form of garden pest control.
(in alphabetical order)
1. Assassin bugs: These ominously-named insects can make quick work of devouring creepy-crawlies many times their size. Packing a powerful poison, the assassin bug ambushes victims and then injects them with venom, turning their guts into a savory soup. Assassin bugs have relatively long life spans and consume massive amounts of garden pests -- caterpillars are among their favorites -- making them a particularly good choice for natural pest control. But beware that the bite of some (but not all) assassin bug species can be very painful to humans, so it's wise to know exactly what you're dealing with before getting up close and personal.
2. Centipedes: All those wiry little legs might make your skin crawl, but consider this voracious carnivore your friend. It dines on slugs, fly pupae, and many other insects that you'd rather not have chomping on your precious plants. And a centipede is quick: Despite its numerous legs, this critter has no trouble moving in for the kill, making a fast feast out of some undesirable garden inhabitants.
3. Dragonflies: These comely creatures love mosquitoes, which is good news for gardeners and all other outdoor enthusiasts. Aphids also rank high on a dragonfly's list of preferred delicacies, along with beetles, flies, and termites. To encourage the presence of dragonflies in your garden, put a rock or two in a birdbath to serve as a dry perch from which a dragonfly can lie in wait for mosquitoes and partake of fresh water, too.
4. Flower flies: Similar in appearance to a wasp, a flower fly (a.k.a. syrphid fly) can be distinguished from its more menacing look-alike by the fact that it can hover helicopter-like in the air. Also take a look at its wings: a flower fly has only one set of wings, while a wasp has two. Flower flies are among your best lines of defense in the war on aphids. They are important pollinators, as well. When planning your plantings to attract beneficial bugs, consider that morning glories, baby blue eyes, and oleanders are among the favored flowers of the flower fly.
5. Green Lacewings: From a gardener's point of view, the benefits of lacewing start early: It's the larvae of these pretty insects that get the job done, with each chomping more than 200 aphids a week over the course of a two- to three-week developmental period. Lacewing larvae also devour insect eggs, mites, and caterpillars, making them a good choice for general bug control. Adult lacewings feed on pollen and nectar, so providing an ample habitat of flowers and a water source is a good way to encourage them to settle down and deliver more of their valuable offspring into your garden.
6. Ground beetles: Another aphid enthusiast, the ground beetle also enjoys meals of termites, grasshoppers, caterpillars, and in some cases, snails and slugs. You might not catch sight of ground beetles at work in your garden while you are, since they hide underground during the day and feed at night. But you can encourage them to take up residence by providing shelter in the form of stones or logs placed right on the soil.
7. Honey bees: Among the most charismatic insects, these fuzzy pollinators can play a huge role in keeping your garden in balance. To identify a honey bee, take a look at the back of its legs, where it carries yellow bags of pollen which is dispersed throughout the bee's daily rounds. Keep in mind that honey bees are not aggressive by nature. If left to their work there's no reason honey bees should be considered a threat to people.
8. Ladybugs (ladybird beetles): The frequent subjects of art, song, and legend, these appealing beetles are voracious predators, each with the potential to consume more than a thousand aphids in a lifetime. Ladybugs also favor mites, chinch bugs, and leaf hoppers, and have no interest in bothering people. Rather than wishing for the ladybugs in your garden to "fly away home," lure them in with their favorite plants, which include marigolds and angelica.
9. Praying Mantis: Close up, it looks like something out of sci-fi horror flick, but rest assured, the praying mantis is a good guy. Those long "praying" forelegs are also custom-made for "preying"; using its lightning-quick reflexes this insect can snag flies, grasshoppers, mosquitoes, and pretty much any other unfortunate garden pest that strays into range, making it a wonderful general defender of your garden.
10. Spiders: Whether they're itsy-bitsy or long-legged, spiders can be a gardener's best friend. Notorious for striking fear into the hearts of man, most kinds of spiders are actually much more beneficial than they are threatening. Amazingly apt predators, spiders cast the net wide, helping to keep many garden pests under control. Spiders like dense shrubbery, hay, and straw, and often set up shop in relatively close proximity to a water source.
Find out which species are the best match for your particular climate and garden, and then let them do their thing! In addition to providing the right habitat to lure these natural predators into your garden, you can take an even more deliberate approach and purchase them. Here are a few options for online bug shopping:
Photo by Scott Bauer. United States Department of Agriculture/Research Service.