If you do not suffer from many light frosts (25-30) or if you do not suffer from one or two hard frosts (20-25) or if you do not suffer from continuous wet cold soil, your plants should survive.

Although your average winter low temp is 38, Palo Alto has been hit by temps below 20 in the last several years.

Joe

I've had Pepper plants survive thru' the winter, but they didn't seem to produce real well the second year. Now I just remove them when I want to work the garden, then buy new ones next spring.

I have one pepper plant that's going on four years old, getting bigger and bigger every year here in Sacramento.

I have small very hot peppers and we call this 'Siling Labuyo' in the Philippines. It has survived 5 winters so far and bears decent crop almost year round, with enough during the winter to tide over. It is planted under the eaves of the roof, in the southwest corner between two walls and under the canopies of my citruses. It can tolerate shady areas which can protect it during the winter. So far the past 5 winters, our lowest was 22 deg F, but our record is 12 deg F. Now with global warming and all, pretty soon we can grow mostly tropicals here, LOL!

I had a productive Thai pepper that lived for 8 years. -It looked sort of like a Bonsai subject by the end though. Currently, I have 2 Thai pepper plants and 5 or 6 Rocoto pepper plants that are 2+ years old.

I have a jalapeño plant that has lasted through a couple of winters in coastal SoCal. I keep peppers in pots, and so I generally replant each year. The serranos I got this year were extremely tiny and very hot - much hotter than the Caribbean (Habanero, I think) peppers that I have. Our average winter low temp is 50°, but it usually gets down to about 45° each winter.

Lars

Our tomatoes and peppers usually survive but don't flourish as well the second year, so we usually remove them anyway. We are in Walnut Creek, where the average low is about 35 or 37F I believe (although we have a slightly milder microclimate due to a cold-air basin draining frost away from our lot). If they survive here, they'll survive Palo Alto.

I am certain that Palo Alto has not only NOT had temps below 20F in the last 5 years, but probably never had temps that low. Our coldest temp EVER was 20F in the big freeze of 1990 (although official temp in downtown was 17F), but in the past five years, we've been virtually frost free. Palo Alto is milder than us.

Still, don't get too excited about next year's crop.

The only truly perennial pepper in the U.S. is the pequin, or bird pepper,(Capsicum annuum var. glabriusculum). These grow wild in Texas and are quite ornamental, as well as being one of the hottest peppers known. On the Scoville scale, jalepenos are 2,500 ~ 8,000 units, while bird peppers are 125,000 ~ 325,000 units, so I wouldn't toss one down casually! These are perennial in the Austin area, which us USDA zone 8, I think, so would survive Palo Alto nicely.

Also, be aware that temperatures affect how 'hot' the peppers will get. Quite literally, the warmer the air temps, the hotter the peppers will be. So even if they survive, the peppers won't be as hot to the taste as if you were growing them in the summer.

If you have them next to a concrete driveway or stucco wall--something that absorbs heat during the day and releases it at night--the soil and air temperature around the peppers will be a little warmer, and that will help them survive.

I plant new ones every year. Like others have said, they don't have the same productivity the 2nd year.

I had pequin, jalapeño, poblano but the cold affected them this past winter. I want to start again this year. I'm thinking Thai pepper and maybe rocoto. I might give pequin another shot- still debating it. Any suggestions? I hate the idea of annuals and starting over every year so the more cold hardy the better.

I know some gardeners in cold climates dig up their peppers at the end of the season, plant them in pots, trim them back quite a bit and keep them inside either in a sunny window or under lights. In my area you can overwinter them outdoors in a protected place, but as most of the posters on this old thread say, I haven't really noticed any benefit to doing so. I generally just restart them every year.

I'm thinking about buying a mini greenhouse just for my peppers. I'm hesitant to bring them inside because i don't want to bring bugs indoors where my houseplants are. I'll decide in the fall.

In zone 9 mine stay outdoors all winter. I have pepper plants that are going on 3 years this summer and look "old". I think they have served their time one earth.

I've noticed that my Habanero peppers get smaller, the older the plants are, and so I've been replacing them with new ones. Right now I am trying to start some new seeds, which I've not done before.

A greenhouse might be a good option - you'd just have to be super on top of opening it up when we have those random hot winter days. Don't need any fried peppers!

This one is two years old,

my mom has 10 year old bell peppers that always have fruit.

How cold does it get for you? I'm in zone 8

I never have frost - last January it never got below 45°, but it got down to 40° last December.