The butterfly garden, in some ways, contained the seeds of its own self-destruction. We had a few plants that performed well year after year, and they weren't necessarily Monarch-oriented: the daylilies, an unknown succulent (over-used in local landscaping), purple cone flower, and cat mint. While they took up ever-increasing space in the garden, the milkweeds and butterfly bushes struggled to survive.
The second phase of the garden could also be called the "state of nature" phase or the "Darwinian struggle for survival" phase. I take solace in tip #139 in Pamela Wolfe's 200 Tips for Growing Flowers in the Midwest: "Don't be discouraged when a plant you've had for years suddenly and for no apparent reason dies." Over time, the process of natural selection and/or the vicissitudes of Kansas weather thinned out our butterfly bushes and swamp milkweed plants. The aforementioned plants also required an enormous amount of water and attention, which made the indignity of their death that much worse.
I relaxed my outdoor gardening efforts during the garden's Mixed Perennial Phase. Weeds proliferated. The soil deteriorated. Darwinian processes continued unchallenged. I thought "what do people successfully grow around here?" The answer --- blaring like klieg lights -- was Rudbeckia, or black-eyed-susans. They command attention, are super tough, and capture some of the aesthetic qualities I love about Coreopsis. My first experience with the Rudbeckia genus was a complete disaster. I tried to sow the seeds directly in the soil but nothing happened.
The next year, I started a number of seedlings inside and tried to bring them along in pots, outside, until they were ready to transplant. They didn't really perform until late in the season, after the tree above them dropped its leaves and allowed long days of full September sun. Then, they grew quickly, stretched out, and occupied a huge part of garden. It was a great way to go into November.
The disadvantage of planting local perennials is that you see the same plants in your neighbor's garden across the way. The garden threatened to devolve into a local four-plant show if I continued on the mixed perennial path, and one of them -- the bee-magnet succulent -- was starting to bore me.
I entertained further thought about the fate of that 16'x6' space. I was looking for a plant that had a full-range of unique and dramatic flowers. But it can't be a water-hog. It needs to tolerate the blistering Kansas heat. It needs to come back year after year, stronger for having made it through another Midwest winter.
I was looking for the perfect perennial.