Not very low if it's a lime. And, in a container to boot. And, you'll not know for sure if it is actually "unscathed" for a bit, as the roots may have been damaged, which might take a bit to show on the canopy. The Mexican lime is about the least cold tolerant citrus going. Not a bet I'd take :-)

Patty S.

And should the plant defy the cold temperatures and live through the winter...the scale will be just fine!

Ok, you took the words right out of my mouth Rhizo!!!lololol

Hello Patty:-)

I had one in a container that was unscathed with 27 Deg F measured by a thermometer I calibrated with a mixture of half frozen rainwater. This tree was "hardened off" by induced dormancy. I have seen limes fresh from the greenhouse get severely burned in a hard dry wind (very low dew point) at 33 to 34 deg.

Patty: I know enough about citrus cold hardiness not to expect too much from this lime, as you affirmed in your reply.

However, I don't think you would have mentioned that bit about damage to the roots if you were familiar with how these fickle early frosts work (I don't blame you because you live in a mild climate, rather I'm jealous!). But basically they are so brief as to leave anything with the slightest covering (such as a layer of soil or the plastic of a pot) untouched. Because they're so tender, the leaves of the lime will surely succomb to the cold long before the roots even reach freezing temps.

Tantanman: I hope I get to compare that 27 degree experience of yours. With my luck the next frost will be 19 degrees and ruin my experiment!

Fab, I spent 10 years in N. Indiana and another 3 in Maryland. Very familiar with early, late and long term frosts, being in zone 5, where I received my Master Gardener's designation :-) Brief frosts probably won't do more than nip your most tender leaves as well. But, you are heading into more winter weather that will give you more prolonged low temps. I think the salient point here was the one Rhizo made - not gonna get rid of your scale. Diligence and fine hort oil applied with several applications will be the better option. I am fortunate so far, not to have to deal with scale. Just white fly, which also is best treated in the same manner. A huge pain in the bazooka, but more effective than any pesticide.

And yes, we're back in S. Calif for a reason ;-)

Patty S.

Last winter was very mild by our standards however the winter prior to that we had a week of sub 32 and mostly sub 20 degree weather. No citrus would survive that. I have often tempted to plant one in ground and build a structure around it for winter. when i have a bigger place that is my goal.

mike

I'm trying to get rid of the plant, not the scale. Instead of throwing it directly into the compost, I am just going to let it die from the cold. I still think I might learn something in the process too, such as how low the above ground parts can survive, and whether sustained sub-freezing weather will be required to kill it. Heck, even seeing first-hand what freeze damage looks like on a citrus leaf and twig might be useful.

Lol...I don't know if "good luck " is the right expression for your experiment or not. I hope it turns out to be a good learning experience for you.