Found a cold-hardy rosemary!

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pepperhead212

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Anybody here love rosemary, try to grow it, but it's too cold in their area? 20º is about the minimum for most varieties. I lost my 15 year old one last winter (the cover blew off the hoop house, in a severe cold snap, and I had just had knee surgery, soooooo...), so I ordered 3 of a good sounding variety from Richter's herbs, in Canada - Hill Hardy Rosemary. I planted one in a 4 1/2 gal fabric pot, and that thing is doing great - better than any other type of pot I have tried! Here it is after about 5 months, from about 4" tall, and I had harvested a lot by this time:
IMG_20181017_103602670 by pepperhead212, on Flickr

But I planted 2 in the ground, and figured I'd cover one, when it gets below 20º, and leave the other uncovered, to see how it does. I did this on Thanksgiving - the only time until Sunday night it got in the teens - but on Sunday night (got to 11º, maybe lower) and all of Monday (only got to 16º, for a high, then back down to 13º overnight) I totally forgot about it! :wacko: So, when I went out there today, I was expecting 2 dead plants, but there wasn't a hint of freeze damage on either of them!
IMG_20190123_120437972 by pepperhead212, on Flickr

Now granted, this is only a brief cold snap, but it's enough to kill any rosemary I have grown in the past, if uncovered. And this wouldn't be resistant in a VERY cold region, but it is definitely a good sign for regions 6-7.

I grew Arp one year (actually about 3 years, but it also died from cold) - the first cold resistant rosemary - but the flavor was not the same. This one is identical in flavor and appearance to normal rosemaries.

Rosemary is one of those "must have herbs", in my kitchen...seems I have too many of those!:innocent:
 
I had a rosemary plant that lasted more than decade when we lived down in Bergen county. It may have been in a micro-climate that allowed for its hardiness, but it looked like a Bonsai tree in its latter years.

One winter got it though. And so many other marginal plants like Hibiscus, and a Cypress.
 
I've had rosemary plants in my yard covered by snow for a week, and survive. What I find is, after a few years, they get very "woody." After three or four years, I pull them and start over, to keep the stems tender.

CD
 
I usually use mine annually. Occasionally one will last 2 or 3 years outside, depending on the winter. When I leave it in a pot, and try to bring it inside during the winter, it doesn't survive. Usually it makes until just about time to get it back outside, then it croaks. Now I usually take cuttings in the fall, root them, keep them alive in the aquaponic system I got going in the basement, then spring comes, and out they go. The downside is Im always starting with a small plant instead of having an impressive bushy plant. Id be interested to see how that plant does through the winter.
 
I'm lucky to live in zone 8b, so the Mediterranean herbs do very well here. I had to cut our bay tree back a lot at one point. We had neglected it and it grew to 30+ feet tall with three trunks! I had no idea it would get that big. It was blocking the sun from my other herbs, so we cut down two trunks and cut back the third. Then the next year, we had an extended freeze which killed it. At least I thought so. Then the next year, it started throwing up shoots from the trunk and now it's more like a shrub.

A friend gave me a cutting from her rosemary plant as a housewarming gift. It got some kind of gall after about 15 years and I had to replace it. I bought one from my master gardener group and it's looking beautiful.

Congrats on your success. I hope they continue to do well.
 
I've had rosemary plants in my yard covered by snow for a week, and survive. What I find is, after a few years, they get very "woody." After three or four years, I pull them and start over, to keep the stems tender.

CD
My rosemary would also get woody, but twice a year I would do a MAJOR trimming of them - around Thanksgiving, and again around Easter, and I would give it to friends, and take the rest into work, and put the trash bag full of rosemary (and sometimes a smaller bag of trimmed sage) by the time clock, with a bunch of plastic store bags, so they could have some fresh herbs with their dinners. After this trimming, the plants would get a huge amount of new growth, esp. In the spring. And some of those long stems are good when they get woody - think skewers for BBQ!

The second plant that I had out there, next to that 15 year old one, was simply an "offspring" of the older one. A form of air layering, this can be done by simply bending a long branch down to the ground, cover it with soil, leaving a generous amount beyond the soil, and it eventually roots. Then, a couple of months later, cut the connection to the parent plant, and you have a new plant, much larger than one started by a cutting. I did this when the large one was about 10 years old, just in case I did have to have another, and that one went downhill (my first one stopped growing after 13 years, due to a root problem). I didn't want to be without, again, though it eventually happened.
 
Good to know! Rosemary's not cold-hardy here, and mine dropped their leaves when I brought them in.
 
I'm surprised that other people have had trouble having rosemary survive when it is brought indoors. I live on the Island of Montreal in hardiness zone 5a. My rosemary has always survived the winter indoors, when I have kept up with watering it. One year, it even flowered when I brought it inside. I do keep it in the pot it spent the summer in.
 
I tried rosemary in pots originally, but they wouldget rootbound within a year - I would have to water them twice a day, but they would still wilt, and the pots were larger than the plants! Didn't have the fabric pots back then, but I'm hoping this one works better. Still, it hasn't been a year yet, though I've gotten more from this than I ever did in the pots back then.
 
I have a had a rosemary bush now for fifteen years, maybe be more. It's very hardy, and the flavours that it emits are very good. What I do when the winter is particulary cold is to cover it with gauze, and that keeps it going until the spring.

di reston


Peeple of ze wurl relax
 
Incredible plant! My plants always flowered in the spring, then again, but a lot less, in the fall.

However, if a rosemary plants is flowering constantly, and no new growth is appearing (seems to happen at the same time, though less in fall), beware - the plant may be stressed out, and went into "survival mode". My first large plant died at 13 years old, and it did this, and when it died, I dug it up, and the roots were being destroyed by something, and ants were throughout the decomposed roots (though I don't think that they were the cause, as they are always there). I also had non-stop flowering in one that was in a pot, and that was due to a totally solid ball of roots, after less than a year.

I'm watching that one of mine in the fabric pot closely, for any signs of this! It would be nice if I could grow it in the pot; if I only had to re-pot it every 3 years or so, like I do my bay, kaffir lime and curry trees (unfortunately, this is the year for the lime and curry trees!), that wouldn't be bad, but not every 8 or 9 months!
 
Those rosemary survived, including the uncovered one! It got to 5, 6, and 9 degrees here three of the nights, and two days it did not get out of the teens, which would have killed a regular rosemary. It wasn't that cold when my old one died - just low teens.

Here are both of them, the covered one on the left:
Hardy hill rosemary by pepperhead212, on Flickr

And a closer up of the uncovered one - a few brownish tips on some leaves, and a few turned a little purplish, but not like the dead, brown ones that extreme cold would normally cause:
Uncovered hardy hill, after 5, 6, and 9° nights. by pepperhead212, on Flickr

This is definitely the most cold hardy rosemary I have grown! That one in the fabric pot is doing great; they say those fabric pots are "self pruning", but only time will tell if I can keep it in a pot for very long, before it gets rootbound.
 
I’m in zone 6 and will try to keep my rosemary alive through the winter by covering it with a large plastic bowl. Will hedge my bet by also taking a cutting indoors.
 
I just re-potted the rosemary that planted in a 4 1/2 gal fabric pot, hoping that might help "self prune" the very small plant, just over 1 year ago. As with all the other rosemary plants I've tried growing in pots, it got rootbound, even though it grew much better than the ones in the ground. Still, I'll settle on the ones in the ground, as it's easier to cover and uncover, than to re-pot it every year.

Here are the trimmings, started! I hated throwing them away, but nobody around uses it.
Re-potting rosemary, 6-23 by pepperhead212, on Flickr
 
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I find it easier to give away trimmings once they are rooted and growing in a small pot. I have no idea how well people take care of them.
 
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