Jo Ann--this is a tough question, especially since it comes from you; such a diversified knowledgable gardener as you. I've read the posts in the other forum, most all of which I use or have tried at one time or another, but the best thing I've found for 'filling a spot' around lilies comes down to the plain old gladiolus planted in groups of 3, 4 or 5. Their bright green spikes seem to camouflage by distraction rather than actually hide any unsightly foliage around and behind them. And besides being dirt cheap, they're low maintainance--I don't save them; just cut the tops and let the bulbs freeze. I plant around over a span of 6 weeks or so just so I have different sizes and a spread out blooming time.
Here's an 'in house' specialty I also use quite a bit. I don't even know what it is but have been told it's some sort of Siberian Daisy. It's an annual and I have to save seeds but it sure fills a hole quickly. I usually plant some in mid August too--just for very, very late flower. These pictures were taken on Oct 24th, and it will continue look good and flower until temperatures drop to 15-20'F, well into Dec. This particular plant is in a wide, open unprotected garden. each flower is about 2 to 3 inches in diameter. Plant gets about 10 to 12 inches high or so.
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