holes in several of my basil leaves
There are holes in several of my basil leaves and some of them are yellow.
Holes in your leaves indicate something is munching on your basil. I am a big basil fan and grow nearly 20 plants each year.
The fragrant basil sometimes attract unwanted bugs, caterpillars, and spiders. I prefer to cover the basil with a light netting to help cutdown on insect damage.
Neem Oil is a good safe product to use in the garden.
Here are a few links to help you.