Answer: The container is a little too small for a clematis plant to remain for any length of time. It will grow there this summer but probably not survive past that. I'd either use a much larger container (twice as deep) or plant an annual vine in the container instead. Morning glory, sweet pea, hyacinth bean or scarlet runner bean will all happily climb up string. Fishing line is a little too smooth for the vines to be able to attach themselves. Use cotton string or jute instead of fishing line.
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