I have clematis in a pot on my deck, which has a southern exposure. I planted it last year and it got three blossoms then died back. This year it's growing like crazy and has one blossom. Should I take the blossom off?
One possibility is clematis wilt—also known as clematis leaf and stem spot. This fungus attacks the plant but not the roots, so it's possible for the plant to die back completely to the ground and still grow like mad the following spring. Damp weather in late spring and early summer seems to activate the fungus. Prune out the affected growth as close to the root as possible. The older the plant the less affected they seem to be by wilt.
Growing plants in containers is much harder than growing the same plant in the ground. Pot size and type, watering, soil, drainage, and feeding are all much tougher to accomplish well with potted plants.
Clematis like to have cool roots in rich, organic soil that is moist, but well drained. They also like to have their tops in the sun. This can be an issue for gardeners with limited exposures. A southern exposure could make the top of the plant very happy but tax the roots. One possibility would be to plant in a thick walled terra cotta pot, shade the pot and roots as much as possible, amend the soil mix with something like Quench to retain moisture, and let nature take its course.