All of the above, as long as you buy them at Publix.

JCTsai,
I gardened in 7a for a number of years, and we tried very hard to have something fresh out of the garden year round. Of the ones you mentioned, I found cilantro is really nice to overwinter, and I have grown it down to about 0F. It is green all winter, and you get coriander next spring/early summer. We cook a lot, and have found freshly harvested, toasted and ground coriander to be many times better than anything you can buy.

Arugula will grow almost all winter in 7a. It does get stronger, some people like that and some don't. As it gets stronger you can eat it cooked.

Lettuce is cold hardy, although the flavor was not as good in 7a during the very coldiest 6 weeks of winter. I would always grow some under plastic, and was able to have lettuce all winter during years with average to above average temps.

Kale is very cold hardy, Dwarf Siberian planted densely has always done very good for me. I was back in 7a over the holidays and we still have a garden there until the house sells. The temps were down to 20F while I was there and they have already had one night in the upper teens and several nights in the low 20s. I picked a bushel or so of kale and brought back with me.

Bunching onions will be good during most winters all winter longer, you may just have to peel off an extra layer in cold weather.

Lemon balm is perennial to about zone 5, although it dies back during the coldest part of winter. I still had some green foliage at the old house over Thanksgiving.

Evening Star Farms is in lower Maryland (link included at end from Southern Exposure Seed about Evening Star) and specializes in winter growing and plant breeding for improved winter growth. I have grown their ice bred rapini, and it did really well. It is big plant and needs a little more space than most rapini.

Here is a link that might be useful: Evening Star Farms

My experience with cilantro is to the contrary of the above, we find it is quite frost-tender. Parsley is about half-hardy (will take repeated light frosts), so in most of florida should overwinter pretty easily without protection. Carrot roots can freeze solid and thaw a few times and still be fine, not that that would ever happen in florida.

It isn't relevant to the OP, but exceedingly few herbaceous plants can take a frost to zero and then thaw without severe damage or death, unless well-protected. I really can't believe that green cilantro experienced zero F unprotected without being killed.

Since the experience I had with cilantro was questioned, I went back and checked the temps for the winters that I overwintered cilantro in 7a. I had a garden there from 2007 thru this year. The historical weather station from wunderground had one location that is slightly warmer and one slightly cooler than my location in west Richmond. I averaged those 2 locations and found 2009 had the coldest temp at 2, followed by 2010 at 6 and 2013 at 8. I think I was growing cilantro by 2009, but don't have any records to show. I planted a packet sometime in the first few years we were there and saved seed each year and also let some self seed. I think I was growing it by 2009, but can't say for sure.

So instead of "about zero", maybe I should have said 5F or about 5F.

This past winter (2012/2013) I believe is a good example of the cold hardiness of cilantro, or at least the variety I'm growing. While 12/13 was not a cold winter in the midAtlantic we had some unusual events that resulted in losing some plants (negreta favas, giant red mustard, ice-bred rapini) that usually survive our winters. We had a very warm early winter. Over a four day period we had 4" of rain that started with above average temperatures and the temperature dropped during the 4 days, ending in a few inches of slushy snow as the storm finished. We then over the next several days had 2 nights in the mid teens. I remember this because I lost the favas and others listed above that usually make it thru our winters. I did not lose any cilantro during winter 12/13, and I had a lot because we have become so fond of fresh toasted coriander we use it several times/week, and thus I wanted to grow more.

Factors I can think of that might be helping cilantro survive for me are:
The area is protected from west and north winds by woods.
The garden soil is 12-18" deep and very rich with lots of organic matter.
Maybe saving/self sowing has allowed the cilantro to adapt overtime. (Don't know - will not claim to be an expert in this area)

In general, I've found that some plants are more cold hardy than what you will find by searching the internet.

I'm willing to share seeds with anyone that would like some.

I have a hard time getting cilantro to germinate and as well it bolts so quick I never have green plants going into winter.

It is hard to believe that cilantro is hardier than parsley, or the perennial celery (smallage) that would likely be killed by 5F, unprotected.

Arugula tastes weird to me, what is the good recipe to adjust the flavor?

I grew lettuce last winter, it grew well, all the hardy vegetables if can cover, I will cover for the hard freeze. thank you all for your replies.