clematis question - support

Kensington, NY

Can anyone advise me about how much support clematis needs? how sturdy?
Heather Y

Prairieville, LA(Zone 9a)

Hi Heather. That depends on the clematis. Some stay relatively small, only climbing a few feet. Others, like sweet autumn clematis, grow to 20 ft long and get quite heavy. Do you know which clematis you have?

Do an online search for Trellises for clematis and you will see there are a wide variety available.

This message was edited Jun 1, 2013 6:51 PM

Spring City, TN

I used cattle panels -- 32' of them and planted a clem every 5'. This was a while ago. Some of them take up a little space, some stretch for miles. Not really, but a good ways.

So I think it DEPENDS.

Big thing is, how are you going to shade their roots? Without shady roots, I can't get them to grow at all. I found clay chimney flues -- think straight-sided bottomless clay pots. I planted the clems in the ground, then fit the clay flues over top of them carefully. They grow like gangbusters.

My grandmother's does so much better than mine, hers gets late morning light and stays very moist. Mine do well, but hers THRIVES. Mine get late morning and early afternoon light and stay pretty moist.

(Arlene) Southold, NY(Zone 7a)

Moon is right - you have to know the name to know the support you'll need.

This is montana grandiflora and you can see the immense size of it. Others are more on the dainty side with many in between.

If yours is in flower now just post a photo and I'll try to help you identify it.

Thumbnail by pirl
Marlton, NJ

Hi, I came across this thread and also have a similar question. I've been thinking of planting sweet autumn clematis along the back fence of my yard to cover the fence. It is a light gauge wire fence almost like a livestock type wire fencing which is supported by metal posts. I was wondering if this type of fencing would be enough support for this type of clematis or if I should maybe attach some type of trellis to it for extra support. Also, I was wondering how many I should plant to cover about 56ft of fence 4-5ft high. Anyone know if I mixed in some honeysuckle if they would grow well together? Thanks.

(Arlene) Southold, NY(Zone 7a)

The fence, as you described it, should be fine but please read all the negative reviews on the plant before buying it.

Ayrshire Scotland, United Kingdom

Until Heather can tell us what Clematis she is intending planting, then I cant see the sense in scaring her with horror stories of the only few Clematis out of hundred's of Species.
Over the last 50 odd years there have been specially grown type Clematis NOT to be too big or go rampant at the site of some light,
I have dozens of these Clematis climbers and are all trouble free, then got a gift of the wild rampant one that almost pulled the roof off the garage after 2 years but, it was easy to get rid of, the flowers, white and hardly seen was most disappointing and there was more greenery than any climber I had ever seen BUT, that did not prevent me buying more Species type and they come in all sizes, colours of flowers size of flowers and shape of leaf.

I would love Heather to get back with what type of Clematis she was intending to grow, her soil type and sun/ shade position. OR as previously suggested, a name or picture of said plants would help.
Best regards, WeeNel.

Prairieville, LA(Zone 9a)

I agree with Pirl. It is a lovely fragrant plant....but it is horribly unruly, grows quickly and sends out underground runners like race cars....a slight exaggeration maybe but close.

I have had runners 10 feet away from the original plant, so know that if you plant it, you will have to tend it rather ruthlessly unless you have room to dedicate to it.

Prairieville, LA(Zone 9a)

Hi Nel. We aren't trying to discourage Heather, or at least that is not my intent.....but in answer to Seanmp's question, I would rather that Seanmp knows how Sweet Autumn Clematis behaves before buying a large number of plants for the backyard fence. One Sweet Autumn clematis could overpower a small backyard.

(Arlene) Southold, NY(Zone 7a)

Nel - it was stated that Sweet Autumn clematis was the one the question was about.

I agree with Moon. Better to be warned in advance.

Ayrshire Scotland, United Kingdom

Ok girls, I apologise, I was referring to Heathers question and not seanmp's, I've smacked the back of my hand for being a silly Billy and will sit in the corner for a minuet ha, ha, ha, chance would be a fine thing just been shopping with my 15 year old grand Daughter and believe me, next time I hear my DH moan about my spending on the garden I'll suggest he goes on a day out with a 15 year old lovely young lady, believe me that's punishment enough, I'm smiling, Jeeeeeees
Best regards. WeeNel.

Prairieville, LA(Zone 9a)

No need for apology Nel....Teenage age girls are very adept at spending....especially when Grandma is paying....GRIN Then there are the days when they shop for ever and nothing makes them happy. Put your feet deserve it. 8-)

Charleston, SC(Zone 9a)

I must agree with those wishing to warn Seanmp (and others) about Sweet Autumn. I have some 30 or more clematis in my small yard (in the city). Except for the Sweet Autumn which I'm still trying to eradicate, all of the others are dainty, light weight, and incredibly well-behaved. I had read about Sweet Autumn's behavior before planting it, but being a newbie then I thought "more is always better". Wrong. I planted my Sweet Autumn at the base of a 6ft privacy fence. The 1st 2 years it was gorgeous.

It covered every inch of the fence for 20ft or more, smothering it in a lovely blanket of snow-like, white blooms. Unfortunately, it also completely covered neighboring plants and shrubs, racing, as someone above mentioned, around the garden covering everything in the area. It was around the 2yr mark that I began to be frustrated at the amount of time I spent ripping Sweet Autumn off of its neighbors. It seemed determined to choke the very life out of everything else in the garden. Then I went around to the back side of the fence and saw that it had actually reached the ground on that side (some 12ft from where it had started on the other side of the 6ft fence). It had rooted in several places on the back side of the fence and started a march across the neighbor's property, which was definitely not a good thing.

I decided to move it to a an area away from other plants (and away from the neighbor's yard). Carefully, I dug it up and relocated it. As a result, I now have remnants of Sweet Autumn on both sides of the yard despite several attempts to eradicate it. Moving it to a spot away from other plants didn't help much, btw. As someone mentioned, the moment my back was turned, it sent out runners in search of things to swallow up. In truth, it can be lovely, and it will definitely cover every inch of your fence. Unfortunately, it will cover everything else, as well.

Heaven forbid you should suffer an injury of some kind as I later did and find yourself unable to do any gardening for a while, as Sweet Autumn will surely take advantage of such an opportunity to swallow up everything in sight. If it can cover both sides of a 20ft section of a 6ft fence in just 2yrs, imagine what it can do in a few more years. During the 4yrs or so that I was unable to tend my garden, my other clematis managed very well on their own, and remained well behaved even w/o pruning (although flower production was lessened). The remnants of Sweet Autumn, however, covered and suffocated several large hydrangeas during that time and even climbed to the top of a very large weeping willow dragging several limbs down - and who knows what else, as I am even now still trying to clean up my garden and rip the Sweet Autumn off of everything else.

Clematis has become one of my favorite plants. As others have said, most are lovely and very well behaved. Sweet Autumn, on the other hand, is extremely aggressive, in my climate at least, and is thus inclined to be problematic. If you do decide to plant Sweet Autumn, you will need to be prepared to be equally aggressive in your efforts to keep it where you want it.

(Arlene) Southold, NY(Zone 7a)

Excellent warning, Dream. Thanks for telling your adventure with it.

Kensington, NY

It is done- I planted it, it is not Sweet Autumn. My Clematis is called " Giant Hybrid Clematic Blue" new to me this year with no flowers yet. It has grown from three inches and no leaves to seven inches and three and a half leaves and quite a bit of stem.

The catalog (Burgess) showed a simple flower 5 inches across, of very pale blue like a Will Godwin, only a more intense sky blue. I loved it. I had to have it. It was described as a high climber, "will vine over and up and around arbors, tree stumps, blooms late June through September.

"Vining over, up, and around" is what the backyard neighbors' roses and grapes are doing.
I like this and I think this clematis will add a nice note to that color mix- but maybe I will not
buy a second one for this roughly 7 x 2 1/2 foot pit .

CONDITIONS:The page describes these plants as more shade tolerant than others - it gets strong early sun, then light to med shade mid day, then late sun when the sun is going to bed.

MULCH: I have mulched it with much that is much less cedar-y than my ususal, actually the stuff smells like chocolate from the cocoa husks!

My SOIL TYPE is an isolated patch against a shared back fence (chain link ( mine) and wood (theirs)) that used to be the compost patch-I had put old leaves, table scraps, ripped up cardboard, so it's a nice loamy little piece of earth-the bottom of the compost keg the composted stuff that did not make it into the main garden when I transferred it- too small- fell down!
It could be the best soil I have.
So that's the story on the Clematis.
cheers Heather

Kensington, NY

Hey Red Clay, is your DG name any reflection of your area's soil? Just asking. I live so close to an ocean I find it quite absurd my soil has so much clay!

I clicked on Pirl's link- it seems as if the clematis variety is autumn blooming or Clematis Terniflora in particular, it could be invasive very easily!

Keeping the roots shady but without rotting using mulch them seems not a problem so far - I know I need more mulch- so many plants are trying to get a start in that patch I am just weeding away!

Heather Y.

(Arlene) Southold, NY(Zone 7a)

Try buying from a more reputable place next time, Heather. That is not a criticism since many of us have bought from Lowe's, Home Depot, Walmart and not been disappointed. There is no clematis (except in Burgess' mind) with that name. Once you have blooms we can help identify it for you.

What a great planting site you have!

You can accomplish the shaded roots with an old piece of slate or a flat rock so that's not a problem. Please mulch! It will save you hours of weeding and save your back and knees. Then you can use all that extra time to shop for more clematises for the future.

Spring City, TN

OK, minor high-jacking here. Heather,

Yes, scratch the surface of any hill around here and it's ORANGE clay most of the time, palid orange mixed with chunks of white limestone, sometimes we call it churt. Now, in the flats, we have a foot, sometimes 15 feet, of rich red clay soil... because in the past, someone would get the brilliant idea to strip-harvest the hills of the trees and the good soil would all wash down into the flats.

I have both. But the house is half-way up the hill, so basically, if I want to PLANT something -- like clematis -- I have to bring in soil... and since we're all on a hill, I have to either terrace or build raised beds.

Now, when I plant down below on the flat, it's stick a shovel in it and plant, baby. Mulch, water, and walk away. That's it. EVERYTHING grows. But it's a long ways from the house, a long ways from water, and although I get to see it when I'm driving in or out, I prefer to have the majority of my plants up near the house so I can water and prune and harvest and sniff and enjoy when I'm around the house.

Thumbnail by etnredclay Thumbnail by etnredclay
Kensington, NY

Pirl, believe me, I know, Burgess. I had to be crazy Right? I read all the DG reviews!

Well I was crazy. I plead temporary insanity.
When this little vine blooms I will send pictures and you will all understand
why I took the gamble, because it seemed that the main problem was a delivery
problem and plants dying en route and when my plant arrived alive despite
a PO glitch instead of a Burgess glitch I planted it right away. It lives.

When we had the concrete removed from the backyard we discovered about
15 pieces of blue grey slate in soil underneath! I keep moving them around using them to edge this and that path way - in front, in back.

Red Clay, My clay is orange as well, but is mostly one shovel-full down -two in the back where I had the soil replaced. It had heavy metals - it had been under concrete- house owned by a family of car mechanics, their elderly mother did flower
gardening along the sides.

"You can get seven cars back there!" crowed one of the brothers as they
sold us the house.

"Garden" I thought, smiling and saying nothing.

This part of Brooklyn is a "bedroom community" for Manhattan which really
took off some 70 - 100 years ago when subway service extended out here and
they subdivided the lots into smallish one and two and three family houses, and apartment buildings on the corners. The previous 300 years it was still rather rural.

Of course you want your plants close enough to enjoy! Good for you ! I love your terraced gardening description- downright Tibetan fix to the "brilliant idea" -and it looks great, too!

(Arlene) Southold, NY(Zone 7a)

Sometimes we do get lured by pretty photos so as long as the plant is alive and you are happy, that's all that really matters. There's enough stress in life without extending it into gardening.

I love the "seven cars" line as opposed to your thought of gardening!

I'll go to Burgess online now and see if I spot it and can identify the real name for you.

My mom was born in Brooklyn in 1898!

(Arlene) Southold, NY(Zone 7a)

Heather - here's the link to Burgess clematis offers. Is the one you ordered the blue one that's shown as #3?

Anderson, IN(Zone 6a)

These are growing on 4 x 4 posts The niobe is at least 7 ft the blue is HFyoung the tag said jackmanii oh well years ago is

The Niobe seeds make "Autumn "

Thumbnail by juhur7 Thumbnail by juhur7 Thumbnail by juhur7 Thumbnail by juhur7
(Arlene) Southold, NY(Zone 7a)

Beautiful! They are both so lush!

Kensington, NY

Yup, Pirl, that's the blue I just had to have! While that lavender color Juhur 's third from left is very sweet, I am hoping for that sky blue!

(Arlene) Southold, NY(Zone 7a)

That's the same one, Heather. It's HF Young.

Anderson, IN(Zone 6a)

Yes very likely it is HF young , and thank you pirl , once again for pointing that out ...
Now I will be searching for jackmanii once again ,, already thought I had been there and done that ! lol

(Arlene) Southold, NY(Zone 7a)

Jackmanii should be easy to find. It's very popular because it's a proven clematis for many years.

Kensington, NY

July picture of the clematis vine - no flowers the first year, right?
Heather Y.

(Arlene) Southold, NY(Zone 7a)

Sometimes there are a few blooms the first year, just to encourage us to buy more.

central, NJ(Zone 6b)

It definitely depends on the climate how Sweet Autumn behaves....I love mine!!! has stayed inbounds, very well behaved growing to cover chain link fence...gets severe trimming early spring

Thumbnail by flowAjen
Athens, PA


How do you get your SAC to stay in bounds? My neighbor has one and it is all over the place. Periodically I see seedling from his SAC trying to come up in my yard. I pull them up or mow them when I am mowing the lawn. His is definitely taking over his back yard. I have many clems, but that is not one I want.

Heather - I have HF Young and just love it. Mine is planted in dappled shade. He is a pruning group 2.

central, NJ(Zone 6b)

I don't know, it just hasn't gone anywhere in the 4 or 5 years it's been there.

Virginia Beach, VA

I do have sweet autumn clematis and they are a pain!!! I can not get rid of them. Dh cuts it down every year. They must have seeds because it invaded my next door neighbors yard!!!

Heather I highly recommend planting SAC for privacy, they are fast growing.

I think we have 5 different varieties and they get pruned every year.


Kensington, NY

I thought I attatched a picture! OK here goes!

Juhur, Carolyn, thanks so much for the NAME!

Thumbnail by HeatherY
Kensington, NY

Update on the HF Young and it's neighbors.
Well I still have no flowers, but the vine seems to be growing happily and making new vines growing right out of the original stem.
Some of the leaves seem to be taking a different shape than the smooth edged oblong ones.
It shares a spot with several other plants, one of which seems to be a weed growing right out of the same hole. I want to be careful!
Anyone know?
PS it is fine to relocate this post if it belongs in some other thread

Thumbnail by HeatherY Thumbnail by HeatherY Thumbnail by HeatherY Thumbnail by HeatherY Thumbnail by HeatherY
Anderson, IN(Zone 6a)

Yes it's leaves will variate especially on young plants or new starts ,
Don't let it get crowded by other plants to extreme ,, all will be well ..
They take some company , just not a bunch ..

Eventually the Clematis will overrun any plants too close to it

(Arlene) Southold, NY(Zone 7a)

Heather - all your photos, except for the last one, are clematis leaves. The last one is highly suspicious but not a clematis.

Kensington, NY

Hmm- highly suspicious is it? I will gently gently pull it out. It is so close to the clematis it seems to be growing out of the same hole. Mulch kept most every weed down and away.

(Arlene) Southold, NY(Zone 7a)

Mulch is such a blessing. An hour ago we bought another 12 bags of it. Now to get it spread!

You'll have to be gentle and if you meet great resistance stop! It's easier to cut it back, let new leaves form and then protect all plants around it with boxes, cardboard, etc. and paint the new weed leaves with straight Round Up. NO tank sprayers or you'll kill the clem's! the photo that I feel has the weed, on the Plant ID forum and get a definite answer before you proceed. In any event, you do not want any other plant competing for nutrients in the center of the clem's!

Kensington, NY

Agreed, Pirl! But Roundup will Never EVER cross my property line.

Post a Reply to this Thread

Please or sign up to post.