Basil Eaten by Beetles

My wife has taken an interest in growing her own herbs and out of about six different varieties the basil has attracted beetles and they seem to be eating away at it and not touching anything else. What can we do?

Try to spread diatomaceous earth all over and around the plants. It has to be renewed after a heavy rain.
If this does not work, try spraying the plants with a neem oil spray, but you will have to wait 4-5 days before harvesting the basil, because if you wash off the neem oil, a lot of the flavour will leave as well.
Last but not least, you could spray the whole area with Scanmask and hope these predatory worms will eat the beetles while they are trying to pupate. Mosquito netting over the plants might be an option if your planting is not too big.