Insects, good and bad, inhabit our gardens in large numbers. I am not fond of crawling/flying things so, good or bad, I usually have to control my response to them while in my garden. Educate yourself, catch a specimen and research it to ID it and know more about it. If you need assistance, take it to a local extension office or contact your local Master Gardeners Foundation. You can get online to review the resources there as well if you are in a hurry or a do-it-yourself kind of person.
It is pretty easy to tell the difference between a honey bee (good) vs a wasp (not good), it can be more difficult to identify all of the remaining insect orders, but it is worth it to familiarize yourself with basic information. When going to war, knowing your enemy is important to waging a successful battle. Weaknesses and strengths will determine best methods of reduction; removal is not necessary.
Is the infestation too much for your garden plants? Crane flies in small numbers will not really harm a lawn, but they reproduce rapidly, which will then be detrimental to the roots of your grass. Healthy plants can tolerate some infestation of bad bugs, but at some point this reaches too much. Where intolerance starts depends largely upon you, the gardener. Do the holes in the leaves of your favorite plant make you want to eradicate every insect in your garden? When you take the time to determine the guilty bug, you can take steps to reduce that population without taking down the innocent, usually beneficial insects as well, which will help maintain that smaller population of bad-bugs. Symbiosis! Make it work for you, your plants and pets will love you for it as they will not suffer the over zealous use of chemicals.
ID is the first step to taking care of a problem infestation. This is true of other pathogens as well, fungi, bacteria, viral, mammal, etc. Know thine enemy. Educating yourself about the proper time and method to reduce the population of the culprit will help you to decide how best to attack successfully.
Determine the habitat that is best for the plants you are protecting, ensure that the conditions are optimal for the plant to fend off the infestation. As with your health, when you are at your best.
Should your plants need extra help, research the appropriate methods and times and determine how able you are to make that happen. Do you have beneficial insects that help control the problem bug? Lady bugs are natural predators of soft-bodied insects like aphids, mites, and white flies. Should the population reach uncontrolled proportions, they can be sprayed with insecticidal soap (home-made or purchased). Using chemicals, ideally, would be a course of last resort. Be sure to read all of the label prior to purchasing and then review when you have it home to ensure proper use and disposal of the container.
Two years ago, when I first moved to this garden, there were aphids in all of the tender plants. I saw loads of ants, some lady bugs and made a mental note to look early the following year to determine how necessary it might be to intervene. The next cool, wet spring, the aphids were numerous, so I sprayed an insecticidal soap on all of the affected plants. In late May, my wonderful husband had been out with a customer in a hay-field that was being cut. He brought me home a video clip of millions of aphids, bright green dots that hummed with activity beyond the noise made by the swather, smothering it as the hay was downed. It was shocking to see so many aphids in one space. Ugh, I went out to monitor my plants with that incredible sixty-second clip burned into my brain. It was pitiful, the ants were as densely covering the plants as the aphid populations and I knew I needed something more potent that the spray I had been using. Within days of the stronger spray the plants were noticeably stronger and healthier.
FYI: Insecticidal soaps are fairly uncomplicated to make, be sure to use actual SOAP, not detergent, antibacterial or other ‘cleansers’ as they can potentially damage your plants worse than the pests you are looking to remove. In a quart container combine about two tablespoons of liquid soap to a quart of soft or distilled water. In places where water is hard the minerals will reduce the efficiency of the soap as it reacts with the fatty acids of the soap to remove them from solution – which is not what you want.
Adding garlic, onion skins, hot peppers, horseradish, cayenne pepper, ginger or other strong root vegetables, by steeping in boiled water, may help repel some insects, but it shortens the shelf life of your spray.
Early intervention and diligence is worth the glory of the healthy garden, be it flower, vegetable or herb.