I'm looking for a plant to mix in containers with white Cleome (4-5 ft tall). My goal is to fill in the center (height) section of the Cleome plants as they drop leaves in the late summer and fall. A tall Cosmos would be a good choice but the fertilizer requirements of the two plants vary too much. I would like to find a plant that flowers in the later part of summer into the fall. I also would like to start the plants from seed. Thanks in advance for any suggestions.

Take care, Pat