There are a variety of herbs that can be used as natural bug repellents, and there are many different ways they can be used.
Top ten herbs and natural pest repellents
6. bay leaf
9. cedar wood
Lavender and cedar wood in particular are good moth repellents. French marigold (which differs greatly from the calendula variety listed above) is excellent for repelling garden pests. Sage is an ant repellent, and bay leaf wards off coach roaches. Most of the other herbs listed above are great general purpose insecticides, and can be used in a variety of ways for this purpose as well.
How to use them
1. There are a many of ways you can utilize any of these natural substances to repel insects. The easiest method, by far, is to purchase, or make herbal oils with any of the above combinations, and burn these in an oil burner or diffuser.
2. Another quick and easy way to utilize these herbal bug repellents, is to simply make a strong herbal infusion (tea) of any one or more of them. This should then be strained thoroughly, and used in a spray bottle. A teaspoon of alcohol (isopropyl or grain) can be added to this mixture as a preservative, if needed.
3. If you are experienced at making your own candles, oils from these herbs can be added to these, making them effective pest repellents as well.
4. If you are familiar with the tiki torches sold commercially with citronella oil, these can be made at home as well. In fact, if you save your old tiki torches, the citronella receptacles can be replaced with any of the above in oil form. All you need are corn cobs, but you must first remove the corn. You then soak the cobs in your chosen oil overnight, and place them in the tiki torches. These can burn as long, and often far longer than the store bought torches.
Source: Over 20 years personal study and experimentation with herbs and natural alternatives.