Donna..it is best to prune the seedheads off...it only stands to reason...why have your vine spend all that energy trying to produce seedheads that you have no intentions of planting?..Pruning the seed heads allows your vine to focus on producing more vines and blooms..which is what you desire...go ahead and cut all the vines half way back on your "Jackmanii" and fertilize with Either Rose Food or Tomato fertilizer and water..you will have another bloom cycle...Jeanne

Jeanne...you're saying cut the vines halfway back and cut off the seed heads? Where do I cut the seed heads? Just under the head or where it connects to the vine? Thanks.

Yes...follow the seedhead down and cut right above where it connects to the vine..and yes cut all your vines 1/2 way back and remove all seedheads if any left after cutting halfway back and fertilize....Jeanne

Jeanne - I decided to give it a try and cut my Jackmanni back as mine was also full of seed heads. I had alot of dead looking vine underneath the greenery - so I cut it back basically in 1/2 - I hope that will be ok?? I have never tried doing this. I fertilized also. So when do you think I should see new growth starting?? Sure looks bare out there - lol. Golden

It seems to take mine 6 weeks after pruning them back....I know..I am getting ready to cut back "Solina" and my "Jackmanii"...This will be their 3rd bloom period for me..that's what I love about being in a zone with a longer growing season!!...Goodluck and let me know...Jeanne

Jeanne , But do you think that cutting it back by 1/2 isnt too much? Hope not cause its done now - lol. Golden

My jackmanii is covering my entire mailbox. If I do cut it halfway back, will the vines grow back to the same height as they were in time for the second bloom?

Yes they should...

Hi Jeanne - I'm telling you, I learn something new every day on these forums! I have had Jackmanni for about 8 years, and I didn't know they would rebloom if I cut them back and deadhead them! They usually look a little untidy now, but this year is the first time I cut them back because they were hanging over the 6-foot fence, and everytime it got too windy, both of the great big tops would fly back over to this side of the fence, and hang from the trellis and wires on my side! I thought the whole thing would come down. Anyway, I got tired of throwing that whole mass of foliage and flowers back over the top of the fence, so I cut it back (not knowing of course that it would help it rebloom!). And as Lynn said, there was a lot of dead-looking stuff underneath (plus I'm sure I broke tons of branches by throwing it back over). I guess I will get out there and deadhead for the afternoon - it's the first day in a long time that the humidity hasn't been unbearable (at least for me). Of course, it can't compare to the heat wave for you all down south - I hope you are keeping cool! Thanks again for the tip.

Judith..you are so welcomed!!..Forums like these are how I learned to grow Clematis..I have Clematis Gurus all over the web...share pics one day..I am sure yours is fabulous and remember to fertilize after pruning...Jeanne

Jeanne - I was just going to fertilize the whole garden with liquid kelp (because it's getting late in the season), is that ok for the clematis? I'm going to order Eleanor's fert. that was recommended on this forum, but only for next year. I would love to see pictures of your clematis (and roses, because you also post on the rose forum!) they must be so beautiful! I am hinting around about a digital camera for Xmas/birthday, but my boys, smart as they are, just aren't very good at picking up hints!LOL So most likely I'll be buying one for myself, and then I will need to learn to post the pictures - I can't wait. I have been taking pictures with a regular camera, but I can't do those gorgeous closeups on the gallery. Anyway, I'll have to be patient...

Judith..LOL..well, just buy yourself a camera as a gift to yourself!!..Or write them a note saying,"Momma would like a nice digital camera as a gift if you are having problems deciding what to get me!"..Posting is easy if you have a site to upload your pics to ..if you don't.... email me and I can give you a link to a site where you can put your pics for free..we will have you sharing pics like mad..yes, My passion are Roses and Clematis..but I also love Plumerias and Daylilys...I have never used Kelp on my Clematis...I bought 4 gallons of Eleanors stuff so I am experimenting with that stuff to see what I think!!..will let you know...I know you are suppose to stop fertilizing 6 weeks before your first freeze/coldspell on any plant as you don't want them go on a growth spurt only to have the cold weather zap them..so they can go dormant at their normal time...anything organic can never hurt tho...Jeanne

Hi Jeanne,

I cut my Jackmanni back but need to fertilize.
Today I got two blooms on my Crimson Star...I'm so happy!
And there are more buds.

Betsy

I cut my jackmanii back, but I think I cut it back more than just half way. I got carried away with my shears and I cut off almost all of the seed heads with those vines. Was I supposed to cut off the dead wood (which I did) or leave it? I also fertilized.

Donnas, Well I did the same thing - lol. so hopefully it will be alright - never tried it this time of the year before. Glad Im not a hairdresser - lol. I got a little snip happy too - I have no greenery left - did you leave any?? Golden

Jeanne - maybe I just might get myself one! It won't be this season though. As soon as I have it in my hot little hands, I will take you up on your offer to show me how to upload the photos. I'm technologically challenged so I hope it's simple. I am going to ask my sons to help me scan a few regular pictures (don't know how they will turn out) and maybe I can e-mail that to you for now? Anyway, I'll post later when I find out how to do it!

Oh Goodie Judith!!..Anytime..just ask...Donna..you did good..if you ever find any dead vines..always prune those even with the soil...nuttin' gonna come of them anyway
WOW Lynn..you really did get prune happy..I know it seems scary..heck the first time I went outside to prune mine back I had to have two double Tangeray Martinis to get up the nerve and wore magnifying glasses to make sure I could see ( I was seeing double..LOL)..but once you see the results from pruning you'll go WOW, look what I have been missing all these years...Jeanne

hi golden ca.. I have 3 or 4 vines left. They were mostly brown BUT covered with greenery, so I left them. They are about 2 feet tall now, where they were hanging over the mailbox and touching the ground. I never really had them spiraling like I wanted. My husband and I went out earlier this summer and tried to get them to climb around the mailbox, but the vines were so tangled up, we said forget it. Jeanne....should I have cut the remaining vines back to the ground since the vines were brown even though there were plenty of leaves??

Hope your right Jeanne - By the way I love your style of pruneing - lol. Scissors in one hand - Martinis in the other - lol. Mindu - I could just loose a finger that way. Your funny :0)
When I do something I do it big - all or nothing

By the way Donnas - one of the books I have been reading by Linda Beutler titled Gardening with Clematis - Linda states (regarding pruning) "If you want a generalization that will carry you right through the entire genus, here it is: When all other logic fails, the best time to prune any clematis - to whatever degree you wish - is right after it has finished its first flowering of the growing season. You wont have to worry about disrupting the flower timing, and there will be more growing season remaining for the plants recovery. Carry this pearl of wisdom with you always" She also says " If your vines have become unsightly they are sending you a message: Prune me this very minute.
So because my plants looked unsightly underneath (really twiggy and sticky looking) - I decided to go for it and see what happens. I will let you know what happens - I decided to try it on 2 of my clems - Jackmanni and Dr ruppel which is a group 2.
Golden :0)

"Jeanne....should I have cut the remaining vines back to the ground since the vines were brown even though there were plenty of leaves??"
Donna..No..the vines themselves turn brown with age but are still viable...those that get pruned to the ground show no leaves and are dead..please don't confuse the two..but in saying that Clematis "Jackmanii" is a pruning group 3 which means every late winter/early Spring it is hard pruned to just an inch above the second or third leaf axil and fertilized...then when the first bloom period is over you can prune all the vines back to 1/2 or 1/3..depending on the look you want for remember that the pruning group 3s bloom on the new vines grown after pruning..you can never go wrong ..it invigorates your vine ..remember to fertilize each time you prune...
Lynn..you go girl...can't wait to see the results of your haircut...Jeanne

I am now just getting a few blooms back on my Jackmanii. I cut it back only about a third. Basically just the blooming tops where all the seed heads were. Unfortunately I did not fertilize at the time of pruning. Is it too late to give it a boost? I also have a Josephs Coat rose that probably could use a good dose too. I hope the garden centers have Rose fertilizer on sale now.

Rule of thumb...always stop fertilizing 6 weeks prior to your first coldsnap!!..Or it will only kill all the newgrowth..How much growing season do you have left??..I don't think enough to fertilize now huh?..Just asking since I live in a much warmer zone than you....Jeanne

We usually do not have a cold snap till about late October (hopefully. Since Jackmanii is a type III and here we prune it to about 8 inches every spring I am not too concerned with new foilage getting snapped.

I read in one of the posts to fertilize with Rose food. What about the Rose fertilizer 'spikes' that you see? Would those be OK or just a one time fertilizer? Thanks

My jacmanni looks the same as the day I cut it back. Haven't noticed any growth, but the foliage is still there and it's still green.

Not sure what kind of clematis I own. One is dark purple and the other is almost lilac in color. I was wondering if it is too late to prune since they are already starting to rebloom. The flowers are MUCH smaller than the first show. Also how do I harvest and plant all the seeds as I would love to multiply my collection especially the darker one.