QUESTION: I know there are some annual herbs that should not be transplanted, but I don't know which they are or why you shouldn't do it.

ANSWER: Some annual herbs, like basil and summer savory, have networks of spreading roots that can take quite a bit of disturbance. But those that depend on taproots, including parsley, chervil, coriander, dill and fennel, are another story. They can be moved only when they are very young, because any interruption of the taproot's progress is likely to stunt the plant.

Instead of producing lots of tasty leaves, transplanted taproot herbs tend to bolt, shooting up flower stalks and rushing toward seed production while they are still quite small. It is much better to seed all of these directly in the garden, but parsley (which is actually biennial) is so slow to germinate that many gardeners start with plants.

If you cannot wait, choose the youngest seedlings, water them well before transplanting and do everything in your power to keep the soil around the root, so it doesn't notice that anything has changed.