Rosemary in the Northern Rockies

Anybody had success with Rosemary (in a greenhouse etc) in zone 4?

Its a perennial in 8b/9a.  Grows several feet high.

Yes I'm aware of this but can they be kept in greenhouse overwinter in zone 4 or must they be brought inside in pots?  How cold can they go?  33 degrees?

I bought a plant several years ago, propagated it with cuttings.  Last year I spent the summer in NY, my neighbor dug up the plants, put them around her house.  I've since taken cuttings from those plants to repopulate my yard. 

The plants have taken several cold seasons, with a few frosts each year.  This January we had a couple of weeks of nightly hard freezes, 20-25 degrees.  All plants are still growing just fine.

I have two plants that I leave in the attached greenhouse of my house. They do overwinter and I have had to severely prune to keep within their alotted space. Should do fine.

In my experience, rosemary will survive down to nearly zero for short periods outside. If you can keep your greenhouse in the high twenties, rosemary should do just fine. And be sure to try a prostrate form as well as an upright. For some reason, the prostrates bloom earlier - I had one that routinely cranked up in January (in the Willamette Valley). A very welcome sight!

in zone 4 my rosemary is in an unheated greenhouse..and does fine..might need a bit of pruning in the spring..but that's what you do anyway..right?

Yeah, some varieties are advertised as cold hardy.

My old boss had a nice patch for market in his unheated cold frame, across the isle from a fig tree... this was in upstate New York, zone 5, in a somewhat cold valley.

asmileisthenewak47 wrote:
Yeah, some varieties are advertised as cold hardy.

My old boss had a nice patch for market in his unheated cold frame, across the isle from a fig tree... this was in upstate New York, zone 5, in a somewhat cold valley.

Wow, thanks for this everyone. This is great news. 

Figs?  You mean there are Figs that can be grown in zone 4 too?  What varieties?

And...how about avocadoes??

When I was working in retail nursery, cold tolerance varied among varieties, with trailing varieties being less hardy, and the more wild upright varieties less so.. the most cold tolerant advertised 15 deg F.  We had a string of nights in the teens this last fall.  New transplants died.  Several more established plants have severe damage windward, but survived.  I think that is the edge of their tolerance.

Hey Seth, are you in Missoula?  IF so, there is a guy selling rosemary at the Clark Fork Market that is zone 5. He is also selling really huge rosemary plants (couple of feet high) that he has overwintered. He'd be a great person to talk to about the whole overwintering thing.

Also, I don't know how well it's going to do, but I just bought a zone 5  fig tree, Chicago Hardy. See how it goes...

i have read that the brown turkey fig might do ok in a greenhouse here..also in the Wayside garden catalog there was a hardy orange, said hardy to zone 5..I'm not sure if that would make it in an unheated greenhouse in our area or not..i'm still kicking around the idea of giving it a try???

I may try it and the brown turkey fig next year..but i still have plans to move my greenhouse this weekend to a new location (over the buried pex in my ground that runs the heated water from the wood boiler in the winter, the ground never froze where that pex was buried all winter long here..so we thought that might be a good location to move the greenhouse to)