I want to address this issue because lots of non-beekeepers land on this site looking for ways to kill bees without using pesticides. This is good news because it shows that people are becoming aware of the dangers of pesticides to our environment, children, and pets. But killing a swarm of bees with soap is not a walk in the park.
If you have stinging insects you need to get rid of, I strongly recommend you call a local beekeeper or a company that gathers wasps for medical purposes. These people will generally come out to your home for free. Once there, they will be able to identify the type of insect you have and either collect it or tell you what needs to be done. If a nest is firmly established in your walls, removing it may be a time-consuming and expensive undertaking. In any case, you will know a lot more after a bug person takes a look.
If the nest is small and outside your home, you can try to kill it yourself with a solution of soapy water (one part liquid dish soap to four parts water) in a plastic spray bottle or garden sprayer. Before you start you need to sequester your family and pets in a safe place and cover yourself from head to toe with protective clothing. Also, be sure no neighbors or pedestrians are nearby.
Soap kills insects because it is a surfactant—a substance that essentially makes water wetter. If you take a leaf and spray it with plain water, the water forms little round droplets. If you spray the same leaf with soapy water, the water flattens out into a thin layer. The wax of the leaf is a fatty substance much like the wax on the outside of an insect or the grease on your dishes—normally water cannot penetrate it. But add soap to the water and suddenly the water and the wax (or grease) form an attraction for each other.
In effect, the molecules of water—with the help of the soap—surround the fatty molecules. In the case of your dishes, molecules of fat surrounded by the soapy water are released from the dish and go down the drain. On the leaf or insect, the molecules of wax surrounded by soapy water allow more water to freely enter the insect’s body. Essentially, it drowns.
The homeowner who tries this method must be aware of several things:
- Death to the insect is not instant. It is going to get mad before it gets dead—so staying covered and keeping family members away is important.
- If you are spraying a cluster of insects, only the outer layer will be hit by the spray. The inner layers of bees are going to attack. If you are covered up, you can keep spraying as the cluster breaks apart but you’re not going to get them all the first time.
- Soaps are different and sprayers are different. You may have trouble if the solution isn’t soapy enough or if the drops are too big or poorly aimed.
Remember that pollinators of many types are endangered, so it’s best to have someone look at a nest before destroying it. If you know nothing of bees and wasps, stay clear of them until someone can identify them. If you live in areas with Africanized honey bees you don’t want to go near a swarm—even to kill it—until someone in the know has assessed the danger.