If the winter is cold and icy, then all the "naturaly" evolution of your citrus is death. Death is a normal course for everything...

Yep...totally agree. If you leave them out, they will perish. They are just not naturally able to handle those temperatures.

7b is very "iffy" for a satsuma, right on the border of what they can survive.

I'm in 8b, plant in ground, and expect to lose everything with those cold winters we get every 10-15 years...as soon as it's getting cold at night, I'd take them in.

I guess I'll plan on taking them in in the coming month but one more question. Last year when we brought them in the key lime somehow got a case of aphids. What would cause this in the middle of winter?

Lol I'll try lot to grow attached to those green plant killing vampires

It depends on the variety of Satsuma, there are some more cold hardy varieties and crosses that have been introduced in the last 10-20 years (Miho, Seto, Orange Frost and Arctic Frost) First two are variants second two are crosses. All of which should survive in 7b with minimal protection once they are grown, most will need some freeze protection the first 4 or 5 years (large C7 real (not LED) christmas lights, covering, etc..) The key lime needs to be inside, they require lots of cold protection outdoors even in 9a.

Your key lime will die at 28F. all satsumas will die in zone 7b when the temperature hit 5F. When you get a record cold of -5F even satsumas in zone 8b will be killed by the 5F that they get.

6b Steve

Sure no matter what zone you live in a all time record low may kill unprotected citrus. The all time record low where I live in southern zone 8b is 8 degrees and that was in the 1940's, The lowest temperature in the last 50 years was 13 degrees, although temperatures in the low 20's are fairly common, and high teens happen every few years..

Ike You are safe with any of

the real cold hardy Satsumas as long as the fruit ripens before hard freezes. In my area hard freezes come from late October to min November

I would not say completely safe, I did loose one of my 4 mature Owari Satsumas 3 or 4 years ago during the big polar vortex mess even though the low was only in the mid to upper teens. Here we have about a 50/50 chance of first freeze by January 1st, although in some years it can happen as early as late October and a hard freeze by Thanksgiving is not uncommon. Of course as I mentioned above there are some new variates that are much more cold hardy than Owari.

Don't do it. You're zone is too cold. They will die, if not one year surely the next.

The problem with cold hardy satsumas and kumquats is that the grafters often use rootstock that is not as cold hardy as the scion and the tree dies easily in not that cold of temperatures.

I would't leave the satsuma out for the winter. I'm in zone 7b too and although tempted sometimes to leave my owaris out, I'm always later glad I didn't because they would have surely perished when that freaky cold blast in JAN came.

However, my brother in law here kept his kumquat in an unheated garage all winter last year, rolling it out in the daytime sun everyday when it got warmer, and his tree is looks like a magazine cover its so pretty. So if there is some protection or shelter, a satusuma could maybe survive 7b.