If you’ve been gardening for any length of time, chances are that you’re familiar with garden pests. You spend the time, energy, and money to plant a beautiful garden, and then baby sprouts are eaten down to nubs, and big, beautiful leaves are eaten down to the stems. It’s enough to make any gardener want to wage war on the pests in their garden. There was a time when I reached for insecticidal oil sprays first, and in hindsight I realize that I was just making things harder for myself. I’ve been adopting practices that more and more gardeners and farmers are using called integrated pest management, and it is the absolute easiest way I have found to manage pesky garden pests.
By using sprays I was contributing to the evolution of insecticide-resistant pests. Those that didn’t get killed carried their genes to the next generation of tiny terrors to plague my plants. I know of gardeners who have turned to stronger and stronger sprays until they were left with a population of pests that didn’t respond to most sprays they tried. Oftentimes when faced with such circumstances gardeners will turn to broad spectrum insecticides that kill everything, ultimately doing more harm than good by also removing beneficial insects from the garden. This practice winds up being time consuming, costly, and doesn’t ever get the job done once and for all.
Integrated pest management (IPM) works just as you might think. Your pest management is built-in to your garden by changing your practices and setting up an environment that encourages beneficial insects. Yes, I still get some chewed leaves, but it rarely gets to the point of needing to do much about it. Chewed leaves mean my plants have become part of a stronger ecosystem. Chewed leaves are also a sign of caterpillars, which means I also get butterflies.
One of the most recognizable beneficial insects is the adult ladybug. The red-shelled beetle with black spots is an icon of springtime that we’re all familiar with. Their larvae on the other hand are less iconic and resemble tiny punk rock alligators ready to chow down on aphids, white flies, and mites. The somewhat similar looking larvae of the delicate lacewing also resemble alligators and have earned the nickname “aphid lions” for their stellar ability to eat aphids and other tiny pests in droves. Last year I had already abandoned sprays, but I was still washing whiteflies and aphids off plants with a hard spray of water. When I started to notice the lacewing in the garden I wondered if I might just let them take over. There were a few weeks where the pest population rose, and I asked myself if I was making the right decision. It wasn’t too long before I started noticing the pests were disappearing and in their place were lacewing in all stages of their life cycle, and parasitic wasps.
While aggressive wasps have turned most people off to the insects, there are some species of wasp that are docile, solitary, and want nothing more than to help your garden. Parasitic wasps are tiny, and you probably won’t even see them unless you’re really paying attention. They earned their parasitic title for their practice of laying their eggs inside other insects, like under the skin of hornworms or in the backs of aphids. Patterson is also home to some wonderful mud dauber wasps, the most beautiful of which is the blue mud dauber. The blue mud dauber may startle you at first as it looks like a gigantic wasp covered in a metallic blue sheen. If left alone, it will be happy to leave you alone -- it’s really just looking for mud to build its nest, and black widow spiders to feed to its larvae. While spiders are also beneficial pest-predators, we do draw the line at our place when it comes to those that pose a real safety concern.
Among the favorite garden friends for many gardeners is the American praying mantis. I liken them to the guard dogs of my garden. I’ve had them be extremely friendly and playful, having one last year that liked to ride around on my shoulder as I worked in the garden; but, they are also voracious eaters that will eat both pests and beneficial insects. Though it can’t be denied that the good they do for a garden is immeasurable, and I am comforted when I see their intricate egg cases which are often affixed to vertical surfaces like the wall of the house or a fence post.
Other beneficials to get familiar with are ground beetles and assassin bugs. Ground beetles can be welcomed by using mulch or growing ground covers, and they will even eat slugs according to a handout from the USDA-ARS Horticultural Crops Research Laboratory. Assassin bugs can often be recognized by their distinct elongated heads. They use quick motions to capture their prey and will be happy to dine on many pests. While they are a friend to your garden, assassin bugs can pose a risk to humans as they can bite and can carry disease -- it’s best to give them their space and don’t allow them in the house.
To attract any of these beneficial insects to your garden, you have to make sure they have a source of food (pests). Some of them can also be welcomed by using insectary plants and a quick internet search for insectary plants will give you many lists of suggestions to add to your garden. If you don’t want to wait for these insects to find your garden on their own, many nurseries will often carry live ladybugs, lacewing larvae, and praying mantis that can be released into your garden. You can find more information about IPM on the USDA website, the University of California Agriculture and Natural Resources (UCANR) website, and at our county agricultural extension or through the Master Gardeners.
Until then, I wish for you the joy and comfort of recognizing your bug buddies and resting assured that your garden is protected. I hope you enjoy learning more about entomology and the fascinating insects that share Patterson as their home.