What kind of rosemary is it? I think that it should make it, if you've given it well draining soil. Forget the parsley, that's an annual-biennial.
So if the rosemary and thyme are in clay pots, with the soil being 1/2 perlite (you can use sand but I don't think it's good)It should be okay. If you can bring it close to the building during the coldest times it would be okay, and what would REALLY work is if you wrap it especially the pot, with christmas lights... that would keep it like 1 or 2 degrees warmer. I think it should survive.

Gosh, I'm so glad you asked this question because it has been on my mind too. I became a first time ever (balcony) gardener this summer, and thanks to this formum I've had great success. Since nine out of the ten herbs I've grown have done so pretty quickly and given me a generous harvest, I don't mind buying new plants in the spring. But the rosemary took awhile to get going, so THAT one in particular I really, really want to try to keep alive so I don't have to start from scratch every year.

I like the idea of putting Christmas lights on it, although winter-like weather is most intense in my part of Virginia between mid-January through mid-March...so I'm not sure that would work to keep it warm for me...but it would be pretty during the holidays!

Heathen1 - Could you explain the rationale behind the clay pot and the perlite? Is this because of snow and other wet precipitation? (I ask because I have a covered balcony and the rosemary wouldn't get any water other than what I provided.) Thanks!

Neither over winter here in my Z6. It may help to bring them inside for the winter months and let them sit near a sunny window and water lightly about once a week. After the end of April, you can repot them into larger pots and put them back outside again. Clay pots help to wick away too much water, if your heavy with watering. I don't like using perlite as its just a filler and might be fine for seed starting in light soil mediums, but once the plants rooting well, you need more rich soil and less airation.

Thanks, ks! I think that given the relatively mild fall and early winter weather here, that I'm going to try to keep it outside as much as possible through mid-Jan. (as long as it stays in the 40s or above...unless someone here lets me know that's too cold) and then move it inside for two months. The only thing I'm concerned about is that the windows I have in my condo home all face east (although I do get plentiful morning sun). From what I've read on here, most people who are successful with growing herbs indoors have southern exposures at their disposal. Oh, well...I'll give it a shot and see how it goes.

Manillesol...good luck with your rosemary! And having been to NYC in fall and winter, if you were planning to keep the thyme/parsley/sage out on the fire escape, I'm afraid they would last outdoors not much less longer than you or I would. Brrrr, it's cold up there in Z6!

Heathen: thanks for the tips...I like the Christmas lights one especially--but do you suggest I keep it outdoors? It gets really cold here as thymewaitsforme can attest :) I'm not sure exactly what kind of rosemary..i'm assuming officinalis..I just picked it up at the greenmarket.

Ksrogers: bringing them inside, do you think that will work for the sage as well?

Thanks for the good juju thyme, I hope your plants work out as well. The difficulty in getting my rosemary to flourish is totally the reason I'm trying to help it survive the winter too! :)

PS: How about the glass cloche/plastic bottle as mini-greenhouse idea? Does that work?

Rosemary overwinters easily in the UK where it withstands temperatures down to and slightly below freezing. 40f would be no problem for it. However it is not tested here by very low temps or by prolonged freezing and the soil rarely freezes at all. My thoughts would be to leave it out any time the temperature is above freezing but to protect it from cold drying winds with horticultural fleece, (Reemay?), and to put it in as sheltered a spot as possible. I would not wrap it in plastic as that could lead to condensation and mould. Nor would I put a plastic cloche/bottle over it for the same reason and also because it could scorch if the sun was bright. Rosemary in winter needs cool light conditions and free air circulation. It should only be 'ticking over', not actively growing as this is what it does in its natural habitat.

I am no means an expert in cold... I thought that thyme was hardy to zone 5. Okay, I googled... I guess the difference is that it's possible to get rosemary to survive in 6b, not so in 6a. In MY neck of the woods, a lot of plants that won't survive 5 feet from the house will do okay right next to the house. The house gives off enough heat to keep the plants warm enough to survive. That's why I thought little tricks like keeping the plant next to the house, keeping it wrapped in lights might help... a cloche might help, but I've heard snow acts like a insulator. I'd wrap the christmas lights through the whole winter. You could even try a heating pad. :D but if it's that bad, it's better to bring it indoors.
Bringing it indoors will shock it. But in my experience, they don't like it much indoors. Rosemary inside gets mealies and has all sorts of problems.So, I'd wait till it gets down near 0º then when you put it back outside, you have to gradually acclimate it, a small amount of time at a time, so that the shock won't kill it.
I'd wait, with global warming, you have no idea what the weather will be. Heck, Sacramento got down to 22 last winter! Even the native plants died all over the place and the native peoples were freaking. :D So I'd wait, you might have an extraordinarily warm winter. Just because your weather can get down to -10, doesn't mean it will.

Oh the travails of growing potted plants on fire escapes! :) Thank you so much for your tips guys! I will check back in during the winter and let you know how the rosemary is doing.

One thing you must take into consideration with your plants that some others might not realize - you're container gardening, and in a big city. Using containers immediately change the zoning considerations for you, although, living in a city warms up the zone by a few degrees, too. So basically, we (I'm a Philadelphian container gardener) should consider plants that can survive up in zone 5, or really protect our plants carefully over winter.

Now, I did have a small rosemary survive three winters outside, only to die on me some time in the early part of last spring! On the other hand, the one I brought in last winter, didn't survive the winter.

With that, I'm obviously not an expert, BUT I have to have rosemary, so am trying again, and studying up on them online. This little gal will be staying on my unheated front porch (western windows) with her ceramic pot covered with bubble wrap. They can withstand temperatures to roughly 0 degrees Farenheit, so you can probably let it hang out on that window sill right next to your fire escape without even wrapping her up. (You will probably want to put cork or something that does expand and contract under her, so the draft doesn't hurt the pot, if it's not plastic.)

As for your sage, thyme, and parsley -- well, have never had sage survive the winter either. (I really suck at gardening, but the more I learn, the less I suck! LOL) The thyme almost made it through the winter inside and, surprisingly the parsley did survive -- but he stayed out on the unheated front porch too.

Of course, parsley is a biennial, so there are only three purposes in overwintering it: self-satisfaction that you did it (my favorite reason LOL), sprigs of parsley on your plate for the holidays, and for seeds the next year! Now, my parsley has been flowering (looks like small green Queen Anne's lace) all spring and summer -- still is. A caterpillar that would turn into a butterfly enjoyed it for a while, until the birds found her, but if you want butteflies (and, yeah! They even come to city gardens! No idea how they find us, but they do come! LOL), it's another good reason to keep your parsley going through its natural life.

Now, don't mind me, but I'm going back into naive mode, and pretending it's not 61 today, is STILL only August, and we have over a month left before we have to start considering what to do for winter time. LOL

Up here in zone 5, my rosemary comes in every winter and does fine though it does get leggy and needs pinching back. I have five of them and they generally start flowering as soon as they come in and keep it up for months.
They are in a south window but east should be OK and keeping them close to the glass will help to keep them cool (mine actually sit on the floor next to a sliding glass door).
Important thing is to have them in a well drained potting mix and not to over water. Or let them dry out. If the new growth wilts a bit, that's OK but it's all too easy to let them get too dry and then they turn up their toes.

In Z6, temps can drop down to less than 10 degrees for several days at a time. Sage, has many variables, so its difficult to tell if it would survive a Z6 winter. Mine never did. I grow both sage and rosemary from seeds and start them about mid March.

valentinebear - are you sure you mean 0 degrees FAHRENHEIT? That's some tough rosemary you have in Philadelphia!

yeah, she does mean 0ºF. :D It's COLD back there!

Its been below zero F here a few times too. About 3 years ago, I lost all my roses due to an extreme cold winter. Some of the bushes were very old and once killed by the severe cold, they never grew back.

Valentine: thanks for those detailed tips! So you suggest I put the rosemary on the windowsill inside or outside? And if I wrap it with bubblewrap, do I wrap the plant too, or just the pot? (It's an old giant tomato sauce can from Lombardi's Pizza)

Oldrose: My window faces southwest, but because of all the buildings around me (I'm on the second floor) light doesnt last very long :P

So I'm in California now guys, San Jose visiting some old friends and it is COLD out here! Something is really up with the weather--this past month has just been World Natural Disaster Month. For the love of Al Gore, let the government set standards already and stop this madness! I came out to Cali for a tan!!! ;)

Now I am really confused. I can understand the weather hitting 0 f but not the rosemary surviving that temperature. If 0 f would kill roses wouldn't it kill rosemary?

Yes, the rosemary was dead. A mild winter here would be down to 15 to 20 degrees, and even for that temp, rosemary will not survive. I have never had rosemary ever survive a single winter here as I said before. For the roses to die, the weather was so very cold that they just never recovered. I don't grow roses much anymore and the only ones left are a few wild types that have survived so far.

It's really going to depend on what variety of Rosemary you have. Some can withstand below freezing temps., so I'm told. I'm going to try to keep my "Arp" Rosemary outside this winter. The Lady I bought it from lives in Northern Michigan and claim this variety will handle -20 degree temps (F). I'll let you all know if mine does! I've also heard that "Hill Hardy" can handle cold Winters. Many Lavenders can't handle cold Winters, but mine does just fine, as does my Sage. I've had both for so many years, I have no idea what varieties they are. Kathy

Thank you everyone, for all this great advice on overwintering rosemary.

Another question...can someone please explain what the terms "woody" and "leggy" mean? I'm not sure I would know what this was if I saw it (so hopefully that means mine is NOT! LOL)

Woody means the stems get hard and are not flexible. New shoots of rosemeary are very green and soft, as well as easy to break and and bend. Woody is the lower parts that hare brown color and quite hard. Leggy means that the plant has long stems and just a few leaves at the tips of the branches. Usually this occurs on older stems or ones that have very long length and few leaves near the base.

Leggy also is used for plants that aren't getting enough sun and stretch towards the sun, weakening themselves.
San Jose is nice, Now if you were here with me in Sacramento, too hot to go out and get a tan! :D I am in my 40's now, more concerned with cancer/wrinkles than tan, but I like getting tans more when the weather is in the 90's not the 100's.

ksrogers and heathen1: Thanks so much for the clarifications on 'woody' and 'leggy'. Very helpful!