Since you received our Garden Notes on Shade Gardening you'll notice that where these are planted are in North Texas. My plant is not a huge colony of large plants. It is a small plant that comes up every year now for the past 3-4 years and produces one or two flower stalks. It grows underneath a huge Ligustrum tree and a large Boxwood. I don't think that any direct sunlight hits this tiny plant, but I'm very fond of it because it was a 'rescue' plant. I think that we get enough cold weather to vernalize the bulb so that it will bloom and the soil where it is planted drains very well; if anything it stays pretty dry most of the time. When you look at the USDA Profile for Lily of the Valley, Texas is not even very near the Southern range for them, so I'm practicing 'Zone denial' and going against the popular beliefs for this plant.
On the other hand, my Solomon's Seal are planted in the Dappled Shade areas of my garden, and they have finally grown into nice groupings that have some size to them. If you have been unsuccessful with Solomon's Seal it could be the accumulation of cold temperatures that you don't get in Katy when compared to North Texas. And I've tried Bleeding Heart in Fort Worth unsuccessfully. But one of my favorite quotes comes from Tony Avent at Plant Delights Nursery in Raleigh, NC who says, "I consider every plant hardy until I have killed it myself...at least three times."

Thanks for your inquiry.

Happy Gardening!
The PlantMaster