Hi Karen! Nice to see you here. Sorry for the delay in responding. I can't see your photos. Hmm.

I've grown it in an area that could occassionally flood. I felt the combination that would do it in, was wet during dormancy. The best culture does seem to be a bit drier though. I have cernuum I've grown from seed in a several areas around my house now. It's easy to grow, it took me four years to flower though from August sown seed. Cernuum is the most moisture tolerant allium I've ever grown, but still...just FYI :)That's the best color I have from the seed grown, the typical is a paler pink. May I suggest some plants? (I still don't know what zone rating the OP has) I do natives quite a lot, I grew hibiscus coccineus (in fact most hibiscus) and asclepias incarnata, LA iris cultivars on the edges of my pond at a past house. They all did exceptionally well (compared to any plantings I've done of these before or since), and I think would thrive in the conditions, I also don't know how much (and when) your rainfall occurs. Other candidates would be lobelia cardinalis and siphylitica. I also had Michigan lily (lilium michiganese) growing not quite in the water, but only a couple feet from it...they appreciate wet feet.Just some photographic suggestions...all photos are my own from my plantings. All these seem tolerant enough to me to be able to handle some dryness along with inundation, though again with different rain patterns than mine perhaps, who knows?

It sounds like a good idea to attach a pipe to your downspout and bring the stormwater into a rain garden in your front yard. If your yard is fairly flat, you could dig a trench for the pipe at a slight downward angle, then add a pop up to bring the water up to the rain garden. I like the idea of putting the garden in the front corner! It looks like your yard slopes towards that corner as well. If your neighborhood has a neater front yard look to it, you could put in short massed plants like canada anemone, fox sedge, wild geranium and blue flag iris.

Along the fence is an option . . .