|MadSci Network: Zoology|
HI.. There are many, many herbs that have been used for insect repellents, to name a few: bay laurel basil cedarwood chamomile clover flowers feverfew garlic ginger lavender mint onions pennyroyal rue sassafras savory southernwood vetiver wormwood These above are normally considered to be the most commonly used. From your list ginger, garlic, onion, lemon grass, clove, pandan leave, chilli and cinnamon; I have also seen lemon grass, and clove used though the clove seems to be used more to mask the odors of other ingredients rather than a repellant by itself. To list their effectiveness in order as general repellants is pretty hard since the results would vary upon method and area of application, type of insects, and other variables. An example is that basil seems to work well on flies and pennyroyal on mosquitoes but the reverse is not true. Economics also becomes a factor. It would considered to be rather expensive to scatter ginger or any large area as a repellant. As far as cockroaches are concerned the most natural way of repelling them is to first make sure that there is not a suitable environment for them to inhabit. Store food products in sealed containers, make sure to keep trash , debris and garbage to a minimum around dwellings. Boric acid, placed around the base of walls works very well to eliminate roaches and is relatively safe though not a natural repellant. There are a lot of websites devoted to herbal gardening and natural product utilization. You may want to search some of these sites since they often list home brews and herbal concoctions that people have used and found useful as repellants. Finally, I donít know about insects, but my wifeís chilli usually creates a gas that repels humans quite effectively about 2-3 hours after you eat it. Ö.. Mark
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