I personally don't think the data out there about the hardiness of clematis in general is worth two cents. Most labels have the generic growing zones of 4 to 9 on them by default. That is why the survey being conducted on COTW about zone hardiness and cultural characteristics of all clematis types is so important. I personally have seen nothing or read anything about Rooguchi being any less hardy than the other types of clematis.

That being said you do have quite a choice. If it were me and I could get a clematis at a great price, I would get it and pot it up next spring in a one gallon sized pot or larger. Then you could wait to see if your Rooguchi survived or not. If so you could grow Rooguchi in a container provided you get one large enough. If this is not possible or something that you wanted to do, you could sell the second Rooguchi or see about swapping it with someone for something else you want.

I think I'll get it - I certainly have friends who will take my extras if mine survives. Or I'll find a spot for it since it's so pretty.

It really bloomed well last year for a new plant and I never saw any hint of mildew.

Congrats on the lack of mildew. Mine draws it like a magnet but I can deal with it by spraying. Now if I can only remember next year to start the spraying proactively instead of waiting until the mildew appears! LOL

I don't know why it wouldn't be. It is an integrifolia hybrid and the species itself tends to be a zone or two hardier than most LFH's. -20F is a zone 5(4) and I've seen 'Rooguchi' listed to a zone 3 as many times as I've seen it listed higher :-)

As Miguel notes, I think many times listed hardiness zones are only guides for climates where a number of gardeners have had success growing the plant, but not necessarily the lower limit of its range. I'm not convinced that 'Rooguchi' has been around long enough for gardeners in colder climates to know for sure just how cold hardy it is. It's certainly worth trying!

No worries, I've had this clematis for several years and it laughs at -40 temps. I'm in an area that generally does not see much snowfall to give additional protection.

Terry

Glad you chimed in here with your experience Terry. I remember back when I was considering getting clematis florida 'Sieboldi' and reading in the Toomey and Leeds Encyclopedia that it was best grown as a conservatory plant and had a zone hardiness rating of zones 7-9. I thought it was going to be questionably hardy in my zone 7a climate and then found out that other people in Michigan were growing it outside planted in the ground. That made me very leary of the hardiness ratings and general information listed about clematis. I am one of those "I will give it a try and see what I can get away with growing based on my experience" people! LOL

Wow, thanks twrosz! We also don't see much snow cover. What snow we get usually is eaten up by the winds. But we don't get down to -40.

Now, it'll be interesting to see if my Vienetta survives. I piled leaves on top of it, like I did last year, but it got way colder this year. If it doesn't survive, I've got hardier clematis waiting in buried pots to put in its place.

Have done this in the past to help insulate brugmansias and I don't see why it wouldn't work with clematis. Get a big 5 gallon bucket or old plant bucket and fill it with leaves. Invert the bucket over the area where your clematis are planted and put a brick or something on top to keep the wind from blowing the bucket over.

nckvilledudes ... I seldom have had a type III clematis perish due to the cold, whether it be of the large flowered kind, viticella, or integrifolia. I must mention I always plant them with about 4 inches of stem below ground ... though, often the viticellas will have several feet of live wood even after -40 temps, these really are such wonderfully hardy plants!

Heck, I'm even trying 'Vienetta' snug up against the south side of the foundation of my home, it's planted deeply and was given a good mounding of soil and I've heaped snow upon it ... will it survive? ... I'll be surprised and disappointed if it doesn't! Unfortunately, it was later in the season when I had come across the small and neglected plant, so it wasn't the healthiest to begin with. I will let you know in April if 'Vienetta' made it through my "tropical" winter :)

Terry

Terry, great info. I was just offering the suggestion however since the true hardiness ratings for clematis are not known and some people may want the extra insurance of the insulation. I have since found out the more common types of brugs usually make it through our winters with no issues so don't use that method any more either.

If you have "tropical" winters, I am not sure what we have here in NC! LOL

Oh, your suggestion is indeed a very good one :) ... until I am sure that some new or expensive plant is tough enough to make it through my nasty long cold winters, I will often protected these.

What you receive there in NC, we here don't call winter, lol

Yeah, I guess it is all relative Terry. For us, what they have even in northern Florida I can't call winter either.

nckvilledudes, do you know what zone those Michigan folks were growing clematis florida 'Sieboldi'? I would like to grow that one and have some Z:5 areas in my yard. Think I should give it a try. I like to push the zones but that Z:7-8 dissuaded me.

I am certain they were in zone 5 at the highest mnwsgal. If you are worried about it, mulch it via the technique I explained earlier in this thread and that should make you a zone 5 at least. Also planting against a brick wall that gets sun will help to serve as a heat sink and radiate warmth in the general vicinity.

Thanks, Miguel, I already use that technique on some of the z:5 plants that I have in my garden beds that are not around the house. Saddly, no brick wall here. I will give it a try.