Mybe not ideal location, or just tired from winter?
I was really looking forward to my clematis season this year since most of my clemtis have been in the ground for three years now and was expecting a good show. I have about a dozen clematis vines scattered accross the yard and have noticed this year in paricular there seems to be a lack of vigor among 4 of them. I have some climbing shrubs or trees and a few climbing trellises and one climbing a rose, but the four giving me the most problems are:
2 (Nelly Moser) planted on opposite sides of the arbor in a low-lying area that faces east that can get quite soggy on rainy days but dries up later (among them are daffodils, hostas, ferns, daylillies, rhodies and two large Austrian pines). One is about 1.5 feet tall and the other barely broke the surface of the ground, this is at least their second summer in the ground. I figuered since clematis seem to like a lot of water, this would be ideal, but maybe not. I doubt there was lots of standing water since the pines and the rhodie do not like wet feet, but the rhodie didn't flower all that impressively either come to think of it.
one clematis (Ville de Lyon) planted in the SE-facing nook by our front door which gets morning sun from sunrise to 1pm or so, it is 2 inches tall. I bought another one at the same time and it planted on the other side of the yeard, it is over six feet right now, and that was the runt of the group. It was covered in snow all winter. I have an aster gropwing at its base which is doing well.
another clematis (Barb Jackman) facing south (planted by roses, tomatoes, and three other clems nearby are over 6 feet. It was over the fence (6 feet last year) but it is only a few inches tall since I had to cut it back so much this spring (wilt). There are irisees and a dahlia next to it.
Anyone in Chicagoland/Midwest facing similar problems? I had a lot of die-back on my roses as well, and am thinking this may have had to do with the winter, but all these clematis are the most protected spots - so figure that out. I should also point out that these vines are in well-ammended parts of the garden and the soil is not hard-pan clay either, it is rocky, loamy, soil teaming with earthworms and organics since these areas have been mulched for over 10 years.