We had upper-teen/lower 20-something temps last winter for several days, and one spearmint plant in the open froze to death. The peppermint (also in the open) came back, as did another spearmint which lives under the eaves.

I wouldn't worry about the mint too much.

My sage will make it through the dusting of snow. Its out in the garden beds. It will look bad but comes back every year. That would be about 5 years I think.
I am growing lettuce and spinach right now and it doesn't mind the snow or freezing temps either.
On the other hand your Hibiscus might have cold issues.

I have a newly planted tree (this fall) that's supposed to be hardy down to 10', but I'm assuming its more cold sensitive b/c its newly planted (?). Should I err on the side of caution and wrap it in lights or frost cloth (or lights AND frost cloth?)?

What is the tree?

Glendale_gardener - I would definitely pamper it based on my experience with a newly-planted "cold-hardy native tree" that perished after the first frost (well not really, it did come back up from the roots, but I wanted a TREE, not a bush).

Tomato question - I have a Roma tomato vine that is LOADED with green tomatoes! Supposed to get down to 30 tonight. I'm torn between plucking all the tomatoes now, or covering it along with a few gallon jugs filled with hot water and hoping for the best!

Juttah, much appreciated advice and I agree. It's a Chitalpa. I've seen references that state cold hardy to 10' and even down to 0'. You think lights are enough or frost cloth too or just frost cloth? The tree is probably 7 feet tall and 6 feet wide at its greatest width.

Challenging roma question. Not sure what I would do maybe pick some and leave some on the vine?

Tomatoes are so cold-sensitive, I doubt anything you do will save it. You could try, but I would pick a lot of the tomatoes as insurance. There are lots of things you can do with green tomatoes, but not much with frozen tomatoes.

I would do both ... I would even use christmas lights and leave them in place until March - might as well decorate!

Good idea with the tomatoes, I think I'll pluck the best/ripest-looking ones and cover the rest. I wish this crazy vine (which I didn't even plant, it just showed up) would've produced like this during the summer. Dang!

If it gets down to 30 the plant will be toast. No amount of covering will help. It happened to me year before last. The tomatoes left out side will freeze on the inside then turn black in a few days, same with the plant. I wish I could say it isn't so, but it is. This is what I do and it works very well.
Pull the tomato plant out of the ground roots and all. Shake off as much dirt as possible. Hang upside down in the garage use a inside wall if possible. All the tomatoes will finish ripping just as if the plant was in the ground. It will make a mess some what, but you will have tomatoes for a few months. I had to do this in mid Nov, I still have ROMA tomatoes hanging in the garage.
We got down to 27 last night and I think it is going to only get colder

This post was edited by campv on Thu, Dec 5, 13 at 15:40

Hibiscus and basil ... they are more sensitive,

Tomatoes - cover or pick.

I'm going all Darwin with mine: it's all going to die if it can't stand the frost. I'll pick the remaining basil, buit the rest is on its own.

It's c c c Cold out there! Hoping for the best; I covered as much as possible, put basil and hibiscus on porch hugged up to house and covered up.

I found some interesting reading on frost protection in the Sonoran Desert.

Stay warm!

Here is a link that might be useful: U of A info on Frost Protection

That's good advice; thanks for posting. I may have missed the "all the way to the ground" part. I don't think it got to freezing here last night. I woke up before 5 to check the temp and it was 39 - or so I hope.

My SO snuck out last night and covered the serrano peppers. And the basil still looks OK. It's my most cold-sensitive plant.

You have to have the covers all the way to the ground, because that's where the stored heat is.

Has anyone suffered any/much damage yet? I've yet to see actual frost on the ground, but the sweet potato vines are kaput. :(

I brought in Epiphyllum 'Curly' last night, and an Edithcolea and a Pseudolithos, but everything else has to tough it out.

No damage at all at my place (N Scottsdale)--even my tomatoes and basil look fine. Bougies, geraniums, etc in pots and in the ground all look fine, unprotected.

We'll see how they look Monday or Tuesday morning as the f-word is back in the forecast for those nights too, grrr.

Happy gardening all!
Grant

Out in my area (Arrowhead, North-West Glendale) all the trailing lantanas (planted in common areas/along the medians) are already showing pretty severe frost damage. Yellow bells too.

Our basil plant is showing signs, but everything else is doing pretty well (even our lantanas-not trailing type-and bougies), but I've been protecting our newest plantings (neighbors have to love our fuscia and yellow fabric tent over our newest tree, lol. And I added some lights too, so it looks like a lit circus tent at night :) Thought about springing for more tasteful frost cloth, but the tree should only need babying this season since its a newbie.

According to the garden thermometer, the lows in our yard were 29 deg (Thursday am) and 31 (this am). At our old house, when our property was 90% natural desert, I cheered for cold temps and snow on the mountains (the colder the better!!), and now that we're in a more developed area with a landscaped yard I worry like a new mom and hope for warm nights, lol, too funny.

My Romas made it through last night and the night before with a heavy Mexican blanket and 2 gallon jugs filled with hot water.

campv, I took your advice and pulled the plant out earlier today; now it's hanging from my unused bike on the porch. I had no idea the plant was that big, or that I had so many tomatoes on it!

Anybody know of any good green tomato recipes? :-)

Glendale gardener, RE: your Chitalpa tree: I wouldn't bother covering that at all. If they can thrive in Vegas (which is considerably colder than Phx), then I wouldn't bother fussing with protecting it in Glendale After all, it's a cross between Chilopsis and ultra cold hardy Catalpa.

I foolishly didn't cover any of my vinca flowers- they're all scorched but not dead. Same for my annual salvias, potted tomato plant. My calendulas and sweet alyssum laugh at frost and are fine.

NOAA says it will be around 37 degrees in my part of town. Trust it or cover up. So far, aside from the potato vine, the only wilt is a few leaves on a pepper. It's been covered every night.

The queens wreath on the arbor froze, so I spent some time ripping it off and stuffing it into the compost bins.

Aaaarrrggghhhh... I forgot to check the queen's wreath on the backyard fence. Oh, well....

Freeze for certain tonight! Cover 'em up or bring 'em in. Thank the weather gods for warmer temps in the forecast later in the week.

I made it through without anything frozen (water, plants, birdbaths, etc), although just barely. Last night (Weds night) it was warmer at midnight than the highs for the last week. Hopefully it's over at least for awhile.

Even my little tomato and basil plants made it. Jack Frost can take a hike back to Flagstaff or Minneapolis!

Fun weather reports! Happy gardening all!

I'm not sure one pepper and my sweet potato will recover, but other than that, all is fine. Maybe not quite; a gentleman friend gave me a potted Thai basil (who sells basil in the winter, anyway?) and even though I repotted it and babied it through the cold nights, it seems determined to die. :(

No real damage anywhere by me this week, thank goodness, although I drove the length of Scottsdale for an errand yesterday and noticed, as usual, the cold pocket around Scottsdale and Shea roads, near McCormick Ranch too. I used to work down there and always noticed more cold damage there due to cold air settling in to that neighborhood. Bougies and lantanas by my house look great, but the ones by Shea/Scottsdale have serious damage (they'll recover). Microclimates are so interesting aren't they?? Looks like a nice pleasant week ahead though, yay! Happy gardening!