I'm a believer in biodiversity in the garden, and I love getting to know new plants. Over the years I've grown and learned about dozens of herbs, and I'll probably spend the rest of my life making new plant friends.But starting a witch's garden can be daunting, so I always recommend choosing a few plants you really want to grow first. If you start with too many plants at once, you might struggle to care for their many needs. And the truth is, I often return to the same plants over and over…