Cover Bougainvilleas at night? Bay Area, CA

[cbrshadow23]

I'm wondering if I should be covering/protecting my bougainvilleas at night or not. Alternatively I could move them into the garage, but this is a lot of work and we're expecting our first baby sometime in the next week.
We live in Fremont, CA where we don't get a "real" winter, but we had a low of 37 a few nights ago. That's about as cold as it gets though. It's our first winter in this part of the Bay Area, so I'm not sure if protecting the bougies is necessary or not.

Below is a picture of one of them from a month ago. Not the best picture but this plant is a real stunner in person and I'd hate to lose it. It's also hard to tell scale, but it's quite large. It keeps pushing flowers but I remove them while I'm still developing branches. I have 3 similar sized bougainvillea that I collected this past winter. I do see bougainvillea in people's yards, so I know they can last through the winter, but these are potted plants. My local nursery told me to protect bougainvillea over winter, but they're referring to nursery stock in 6" plastic pots.

Anyways, what're your thoughts? Should I bag these at night and remove the bag in the morning?

 

[leatherback]

Do you get bougies there in the gardens? Then no worries, leave open and about.
In general , if you do not get frost you should be fine.

 

[cbrshadow23]

Do you get bougies there in the gardens? Then no worries, leave open and about.
In general , if you do not get frost you should be fine.

Yes people keep them here in their gardens. The ones I have were collected from people's gardens nearby.
Does it make a difference that the ones in people's gardens are planted in the ground? I figured being in the ground could protect the roots from getting too cold.
I guess what I'm having a hard understanding is:
A) Advice from local nursery to protect their potted (but very young) Bougies
B) Seeing lots of bougies in people's yards locally

I don't believe we ever get a true frost in this area. Will a single night of frost kill a plant this large? If so, I will have to keep a close eye on nighttime low temps this winter to be sure.

 

[leatherback]

A night of frost can do some damage, which is what you would want to avoid I wuold say. Mine come indoors before frost arrives.

 

[MrWunderful]

No. No tropicals around here need protecting. My portys have been outside their whole lives without skipping a beat.

That includes them getting down to 30° on one night one year.

my mom has multiple potted Bougainvillea that have never been covered in 15 years.

 

[cbrshadow23]

Well it looks like I'm overthinking it. I'll just leave them alone then. Thanks, guys.

 

[Leo in N E Illinois]

Bougainvillea come from Brazil through Peru and south into southern Argentina. In the Argentina part of their range they experience frost at night in the winter. I would not worry about your bougainvillea in your climate. But if you hear of a freeze coming, 29 F or colder, then bring it in. I'm sure the news media in your area would make a big deal of a forecasted night that cold, so you will be safe largely ignoring the bougainvillea for the winter. Don't worry.