Stop! Take your hands off the nozzle and move away from the bug spray. I know you see that insect on your prize rose bush, but can you identify the critter and do you know if it is actually harming your plant? Those of us who garden in the South are always challenged by a variety of pests that seek to make our garden a target for damage. Many of us, at the first sign of garden insects, head for the bug spray. When we spray, we kill both good and bad bugs. Good bugs? Yes, an overwhelming majority of the insects you see in the garden are actually beneficial insects that prey on and eat the insects that are causing the damage to our garden plants. For example, aphids (which are “bad” insects) are a delectable food source for ladybug larva (“good” insects). Spraying upsets the balance in the garden, killing the good with the bad.
Pests in the garden can be managed naturally if you take the time to learn how to support the beneficial insects and birds that will keep pests under control. Here are some tips on “green” methods to tackle pest insects in the garden.
Plant a diverse landscape. When you plant a variety of plants, particularly native plants, you are providing food for beneficial, predatory insects and birds. As they are drawn to your garden, they will, of course, begin eating the bad bugs you are so worried about that are attacking your plants. Dill, yarrow, fennel, tansy, butterfly weed, sunflower, cosmos, foxglove, lemon balm, parsley, lavender, zinnia, purple coneflower, ice plant, Queen Anne’s lace and coriander are some of the herbs and plants that are magnets to beneficial insects and birds. Native trees provide shelter for birds that eat your “bad” bugs. If you do one thing, plant an oak tree (Querus). It supports more wildlife than any other tree!
Learn to identify the most common “good” beneficial bugs that will kill the “bad” pest bugs in your garden like aphids, Japanese beetles, cutworms and more.
Beneficial insects are either predators or parasites. The predator will eat or kill insect pests and the parasite will use the bad insect as a host to complete its life cycle, killing it in the process. Beneficial insects you want to attract to your garden to eat the “bad” bugs include:
- Assassin Bugs
- These attacking bugs sneak up on their prey and use their beak to puncture the bad insect with a toxic fluid that breaks down its tissue. The assassin bug then can suck out the fluid and kill the bug. They do bite, so when you see them in your garden, try not to handle them!
- Ladybugs (lady beetles)
- They are natural predators of aphids, scale bugs, and other sap-feeding insects.
- These bugs have delicate, transparent wings that look like lace. They eat aphids, mites, scale bugs and other “bad” insects.
- Ground Beetles
- These are black beetles with hard shells and are NOT cockroaches. They are active at night and eat caterpillars, snails, slugs, and grubs. The ground beetle larvae feed on insects below the ground.
- Parasitic Wasps
- There are many different parasitic wasps but one, Aphidius colemani, specifically targets aphids, a bug that destroys many of our favorite plants. The female wasps lay their eggs inside aphid nymphs and the wasp larvae feed on the nymphs.
Monitor your garden using the Integrated Pest Management (IPM) approach. This method is simply a common sense method of managing insects and diseases in the garden. If you want to try the IPM Method, start doing the following:
Monitor your garden for signs of trouble. You should be out in your landscape at least once a week looking for signs of insect damage or disease. By carefully observing your outside space, you can see problems that are just starting before they become difficult to control.
Identify what is the problem. If you don’t know what it is, how can you effectively treat it? Remember, most insects and organisms in the environment are NOT pests. Many are actually beneficial and help plants deal with damaging pests. Don’t spray at the first sign of a bug or disease. Identify what it is, where it lives, how it lives and what its life cycle is.
Did you know that most damage to our landscape is done directly or indirectly by humans? We are the pest! When my mother’s plants seemed to all be dying back about three feet from the ground, I did some detective work and discovered that the cause of the damage was spray drift from an application of turfgrass weed killer that had been sprayed on her grass on a windy day. So, be a detective and identify what the actual problem is and the source.
Evaluate and predict the extent of the problem. When you see potential signs of damage, ask yourself some questions: Is it really a problem? Will it become a problem? Can I live with it? What is my “threshold for tolerance” – i.e. can I ignore the look of the leaf damage on my hydrangeas if I know it is not really damaging the plant? What controls are available for the specific problem? Are there less invasive ways to treat without using synthetic chemicals or is the problem severe enough that I need stronger measures? What are the costs and benefits? It basically comes down to your attitude toward the problem.
Decide, and choose how to deal with the problem. There are many ways to deal with a pest problem. You may need to use a pesticide for a severe infestation, but view it as a last resort after trying other control methods.
To learn to identify insects in your garden, purchase a copy of “Insect Identification Guide for Southeastern Landscapes.” Click here to purchase this resource. Click here for more information on Integrated Pest Management.