Clematis, Jackman Clematis, Late Large-flowered Clematis 'Jackmanii'

On Jul 29, 2016, landscapergal from Silverton, OR wrote:

I have had 4 of these in different locations. 1 was in Mt. where it was 20 below for a month and didn't phase it at all..Well over 6 ft. and very thick with blooms. Didn't always cut it back in the spring but no matter is still kicked butt.The second place (hostile alkaline clay soil desert but not quite as cold as Mt but close) and it grew OK. Here in Willamette Valley Oregon I planted 2 this year and they are already 4 ft. and bloomed( I'm deadheading today) I can see I will need more supports for one of them. I love this Clematis and would highly recommend it. I have bought them from several places. I do however plant low growing plants around the base of it to keep the roots shaded. The one in MT had Aconite (Monkshood) around it..They bloomed around the same time and the effect was s... read moreensational!!

On Jul 15, 2015, paula2007 from Silver Spring, MD wrote:

Had some trouble first couple of years because rabbits liked fresh sprouts but after putting a low wire enclosure around it took off. Don't know about recommendation to hard prune since the old wood produces much of the new growth the next year. Now it blooms from spring to fall with abundant deep blue/purple flowers. Looking to propagate these for more blue perennial color in garden. Seeds did not grow next year so trying cuttings next.

On Jun 10, 2013, AstilbeHere from Toronto,
Canada wrote:

I have a couple of Jackmanii: one crawls up through a daphne and one on a trellis. I have a Hagley Hybrid too, which I really don't look after, yet it puts up its flowers in early June. The best clemmies are the species types. Macropetala (Blue Bird - Bred for the Canadian prairies, so very hardy, in a sunny south facing aspect) and Alpina (Francis Rivis, Rosy O'Grady) varieties come in pink, deep red with white or cream centres. All are reliable, although mostly spring bloomers. The tangutica and the autumn clematis are both great late summer performers, but need a good haircut in early spring. Grow very tall. Just about to try a Betty Corning; seen it do well in Toronto gardens. None of the species varieties seem to get the sudden clematis wilt (some of you talk of wilt and brownin... read moreg off...it's a known issue with large flowered hybrids, but fades after a few years when the plant gets established and stronger). Try the herbaceous Heracleifolia varieties. The are not climbers and do well in a perennial border planting - small, plentiful blooms. Note: don't use weed whackers near clemmies (can bring a quick end to the season).

On Jun 10, 2013, mensamom from Laurens, SC (Zone 7b) wrote:

The Jackmanii that I planted about 5 years ago had sporadic blooms until this year. I don't prune it unless it starts taking over something it shouldn't. I did add some organic fertilizer to the ground around the plant's base last fall. And this year I have an explosion of purple flowers. Don't know if it was the fertilizer or if this plant is really a "late bloomer" - pun intended!

On Jun 9, 2012, Cesarsmom from Concord, NH wrote:

I am so glad I read this page! I never knew clematis needed to be cut back! Mine used to almost cover the chain-link fence where it is planted and bloom its head off, but it has become skimpier each of the last 3 years or so, and this year it is a shadow of its former self; now I know why -- I have never pruned it! I am preparing to move and will certainly want clematis in my new location, but now I know what to do to keep it vigorous. Thank you everyone!

On Apr 17, 2012, outdoorlover from Enid, OK (Zone 7a) wrote:

OMG!!! I can't believe I found the name of this clematis. I bought it around 2006 from Sam's and it did not have a name other than "clematis". It has been growing to beat the band since then. People stop by our house and ask what that plant is. It is awesome. Since we moved I have been sad because I did not bring it with me. Today I started looking at new clematis' to buy and plant and saw this one and it is the same as my old favorite!!!! I'm so excited! Ordered two of them!!! It loves living in our area and blooms its heart out.

I ordered them from Bluestone Perennials and they said this plant immigrated from England in the 1850s.

On Aug 15, 2011, herbella from Albuquerque, NM wrote:

I read that this variety of clematis was supposed to be able to survive in the arid climate of Albuquerque, New Mexico and in our poor, sandy soil. Alas, all three of the plants that I bought died, although I planted them in different areas of our garden. It was an expensive lesson.

On May 31, 2011, coffinitup from Pahrump, NV wrote:

Grows beautifully in our intense heat in the desert, just a few miles from Death Valley

On Nov 22, 2009, bonehead from Cedarhome, WA (Zone 8b) wrote:

I grow this at the foot of a lilac for support, the clematis literally covers the lilac for a second 'bloom' in June-July. I've puzzled more than one person looking at the lilac leaves but seeing clematis blooms. In spring I just cut back hard and pull last year's vines from the lilac before they put on their own show.

On Jul 27, 2009, Marlina from Blaine, MN (Zone 4b) wrote:

My plant gets better each year this has got to be the best one for Minnesota.

On Sep 14, 2008, gardenlady123 from Plainwell, MI (Zone 5b) wrote:

I thougt my Jackmanii died!!! But was I surprised when it blossomed the best its ever blossomed before. Georgeously. I do not know how many flowers were on the vine this year. (2008) I know now that I have to prune it in the spring time. Will do that next year. Love this clematis.

On Aug 18, 2008, Ladybeetle from zone 7, TX wrote:

My 'Jackmanii', which was purchased two years ago,started
up growing just fine and it had a total of 3 beautiful blooms! The plant continued to remain healthy but quit growing and quit blooming. I have it facing west so it gets all afternoon sun till about4 or 5pm. The roots are in the shade and the ground is moist. Last year I had just a couple blooms also. I mulch with decomposed horse manure mixed with sawdust.

On Nov 26, 2006, JasperDale from Long Beach, CA (Zone 10a) wrote:

For years I thought we couldn't grow Clematis here in So. Calif. Mine is coming up on it's 4th year and is doing great. I have it in a Southern exposure, tops in full sun and roots in shade of a dwf. Abelia , and it grows up into a pink Dream Weaver Rose. It gets better every year. I am now going to try other varieties.

On Jun 28, 2006, nanabest1 from Clarkston, MI (Zone 5b) wrote:

We planted this clematis in our shade garden with dappled morning sun.
It climbs the arbor and produces very large blooms, it's stunning.
nanabest1 in Clarkston, MI

On Feb 14, 2006, TBGDN from (Zone 5a) wrote:

This is the first clematis I ever bought in 1985. It has since been divided at the root mass (a major job: very tough!) in very early spring, and made into several separate plants. I've l lost track of how many 'starts' I have given away to gardening friends. It is unquestionably a favorite of many gardeners. I understand it has been around for a very long time, and with its great growth and blooms not surprising. I am a firm believer in keeping the roots heavily mulched and/or shaded to retain proper moisture and protected from hot sunlight.

On May 10, 2005, silverbyrch from Portland, OR wrote:

I inherited four clematis plants from my parents last fall and the jackmanii was one of the them. Like other's have noted, they like their toes cool and their heads to be warm. My parent's said it may take a bit for the plant to establish itself and get comfortable in the garden so I really didn't think much of the growth habit per se, I just kept an eye on it and noticed how well it liked the new home.

This year? The goofy thing is having a party of its own! I love it! It's growing beautifully and climbing hardily all over a portion of my backyard cyclone fence. Thankfully it's helping hide the ugly tin shed in my neighbor's back yard. The clematis has not come into bloom yet, but I expect it will within the next couple weeks.

On Sep 10, 2003, jbyrne from St. John's,
Canada (Zone 5a) wrote:

Had a bit of a problem with it this summer (2003). It is its second year and began to grow vigorously until it suddenly became black and died out; am unsure of the reason. Luckily, a few new shoots followed so the entire plant wasn’t killed.

On Jul 10, 2003, gsanch wrote:

I am having a lot of problems with powdery mildew. I have it in some shade...possibly too much?

On Mar 26, 2002, Terry from Murfreesboro, TN (Zone 7a) wrote:

Clematis jackmanii is a hybrid species introduced in 1862, and is arguably the most popular Clematis in cultivation.