Tarragon comes back, as I found out by surprise when it appeared in the middle of a spread of calendrinia. Fennel reseeds and also grows side shoots. I have fennel coming up in a crack in the patio. Parsley can last 2 years. It will go to seed when it's done. Not sure about the garlic.

Here is a link that might be useful: parsley

Yup, tarragon and fennel are perennial, while parsley is a biennial. I assume we're talking bronze fennel, that is. Garlic will be fine, though I undestand that if left in one spot without any harvesting for years you just get lots of little bulbs because they crowd each other. When you plant it, you plant one clove, which becomes a head of several cloves by harvest time. So then the next year you would have a bunch of cloves al close to each other, all making heads of several cloves. I've pulled out the smallest in such situation and left the bigger to make reasonable size heads, or harvested the whole bunch early for green garlic. Cheers!

If I have missed something like garlic (or potatoes), I pull it if it is in my way. The garlic will not form a large head, too much competition like over-crowded seedlings but is still edible.

I know that California's climate is different from mine even though our zone is the same. But, that being said, I can only grow parsley well here in the winter. When hot weather moves in, it either goes to seed or dies altogether. Tarragon and fennel are notorious for disliking our hot humidity. I don't expect the humidity is a problem for you, but maybe...

Garlic is typically planted in late fall, grows through winter, bulbs up in spring, and then is harvested in early summer after the bottom leaves of the plant turn brown. I would think you ought to dig any garlic left from last year and use it.

I would leave the garlic until the leaves/blades turn yellow then lift it & cure it. Replant it in the Fall,Sept. or Oct. in a roll 1 inch deep & 6 inches apart. Use compost & well watered if it is a dry winter.

Yup, tarragon and fennel are perennial, while parsley is a biennial. I assume we're talking bronze fennel, that is. Garlic will be fine, though I undestand that if left in one spot without any harvesting for years you just get lots of little bulbs because they crowd each other.

Perfect! Thank you all! Just what I needed to know! Nancy