Answer: You can't erradicate pests from the garden as there are always plenty more to replace the ones you eliminate. However, when a specific pest reaches a point where it is doing significant damage that warrants control, there are several control options to consider. The key is to make sure the product you choose is labeled for the pest and for the plant you will be spraying it on.
For aphids, the safest of these options include insecticidal soap, horticultural oil, a strong blast of water to dislodge the insects, and products containing neem.
Beetles come in many different species. What works on one species may or may not work on others. With this in mind, your options for beetle control include neem, strains of B.t. for beetles, beneficial nematodes, and rotenone/pyrethrin sprays. If you can describe specific beetles and the plant(s) they are attacking, we can be more specific in the preferred control option(s).
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