When and how should a purple Jackmanii be pruned?
This article should help: https://www.gardeningknowhow.com/ornamental/vines/clematis/pruning-clematis-vines.htm
Just planted a clematis plant. It has several funny looking green balls on it. Should I cut these off?
I think it's probably a seed pod. Many people think they are pretty and leave them on the plant, others take them off. Hopefully these articles will help: https://www.gardeningknowhow.com/ornamental/vines/clematis/growing-clematis.htm
I purchased what I thought was a Clematis, so the tag stated, over the summer. I have had Clematis before, and was a little confused by the leaves on this one. However, this plant began to get little tiny looking (seed size) buds on it in clusters. Nothing happened until the other day. I went out to water and found little pea size purple and pink berry looking things on it. What have I planted???
From what you've described, it sounds like porcelain berry. This article has description, culture and pictures: http://www.missouribotanicalgarden.org/gardens-gardening/your-garden/plant-finder/plant-details/kc/r350/ampelopsis-brevipedunculata-var.-maximowiczii-elegans.aspx
How do I plant clematis seeds?
These two links should answer your question: https://www.gardeningknowhow.com/ornamental/vines/clematis/propagate-clematis-cuttings.htm
I have clematis in a container on my balcony, first year, and it's on a trellis. It did great all spring and summer. Should I cut it back when it dies (it's halfway dead now), or just leave it and let next spring tell me what to do with it? Thanks!
It really depends on what variety of clematis you have. This article will guide you on how to prune yours:
https://extension.missouri.edu/extensioninfonet/article.asp?id=1452
I live in PNW (western WA) and bought an Apple Blossom clematis. It did not look too healthy. I planted it and I now see some flowers forming (near ground level) but there has been no vertical growth. It does not look good. And although I know this type of clematis requires little, if any, pruning, I am concerned about its condition. Can I cut it back now, or wait until after spring to stimulate growth?
Hold off pruning until early spring for most types or following bloom in others. While it should not hurt the vine, depending on the type you have, blooming may be delayed or skipped entirely the following season if cut back too early. It may just be in need of some fertilizing too, which should help give the plant a jump start with growing.
I have ordered an arbor (84") to place over the path leading from our front gate to our patio. Placement of the arbor will depend on the sun and trees in our yard. I have chosen to plant Nelly Moser clematis to climb this arbor and I would like to know: do I have to plant one either side of the arbor so they will eventually meet at the top, or should I just plant on one side of the arbor so it will grow up an over to the other side?
This is really up to you, though planting one on either side will speed up the coverage. For additional information on growing and caring for clematis vines, these articles will help: https://www.gardeningknowhow.com/ornamental/vines/clematis