I have a very beautiful blooming clematis but it has been around for years. I am wondering if you can ever completely chop off all vines to just about 2 inches from the soil to give it a fresh new start with new growth right from the base,since the vine stocks have slowly sagged downward to the base of the vine over time.
Pruning does differ with Clematis varieties.
Here is an article that will help you with regular pruning.
https://www.gardeningknowhow.com/ornamental/vines/clematis/pruning-clematis-vines.htm
I will tell you that I have also had some mature Clematis, varieties are unknown, that had also become a tangled mess and I needed to replace the trellis supports.
I trimmed them back to 12 to 18" in height. Although I had less flowers for a year or two, my vines are in much better shape and have recovered completely.
I find Clematis very hard and forgiving. I am in a zone 4 garden, so no pampering here!
my clematis bloomed in spring and I am delighted to see more blooms coming now, should I de head the old blooms
Yes deadhead clematis flowers as soon as they are done blooming. This article should help:
http://www.gardeningknowhow.com/ornamental/vines/clematis/pruning-clematis-vines.htm
I have a clematis vine which bloomed beautifully at first but now the flower petals as well as the leaves are very thin and sickly looking. What is the problem?
Here is an article to refresh you on the care requirements.
https://www.gardeningknowhow.com/ornamental/vines/clematis/growing-clematis.htm
https://www.gardeningknowhow.com/ornamental/vines/clematis/types-of-clematis-plants.htm
https://www.gardeningknowhow.com/ornamental/vines/clematis/clematis-winter-preparation.htm
I have abundant green foliage on my climatis, but few flowers
This article will help you pinpoint the cause.
https://www.gardeningknowhow.com/ornamental/vines/clematis/getting-clematis-to-flower.htm
I have a lovely clematis in a large pot out my back door it has improved and this year at its finest ,I feed well and only lightly prune it started to bloom and had lots of buds , then all of a sudden it has started to wilt , it has been like this since the last heavy period of rain can I get it to recover or will I loose it
Make sure the soil and pot are well draining. If the root sit in soggy soil, they can die from root rot.
Check the soil, is it wet?
Placing the pot on pot feet or even up a couple of bricks so that water can drain may help .
One of my 2 year old clematis flowered for the first time a few weeks ago . The blooms lasted 2/3 weeks and then the plant started to darken and brown rapidly and now appears to be dead . The other plant appears to be very healthy , they are both in the same bed against a wall and have both been treated the same .
Watering issues is the most likely issue. Make sure the soil is moist but not soggy; and that the soil is well draining.
Excess moisture could lead to root rot or even fungus issues with the vine.
https://www.gardeningknowhow.com/ornamental/vines/clematis/growing-clematis.htm
Planted clematis last year and had a few flowers. Flower card stated it was a tall height clematis a "gran altura. Did not prune it for unsure of what I should do. Spring this year brought beautiful purple flowers and since then no flowers. Very heavy rains for a week, could that possibly be responsible?
Poorly draining soil can effect the health of the vines roots.
These links will help you.
https://www.gardeningknowhow.com/ornamental/vines/clematis/growing-clematis.htm
https://www.gardeningknowhow.com/ornamental/vines/clematis/getting-clematis-to-flower.htm