Ask Mr. Smarty Plants

Our top three choices for the conditions you describe are Packera obovata (roundleaf ragwort), Chasmanthium latifolium (Inland sea oats) and Physostegia virginiana (obedient plant).  Depending on how well the soil drains in that area and how much moisture is there year-round (wet all the time, moist, alternately bone dry/standing water), at least one and perhaps all of them should do well in your narrow strip of wet shade.  Roundleaf ragwort (also called Golden groundsel) is one of the earliest flowers to bloom in the Spring, creating an ethereal golden glow when planted en masse.  It will spread to create an evergreen groundcover under the right conditions and so could potentially be used alone.  Obedient plant and Inland sea oats are attractive and tolerate both wet and dry conditions well and are also good spreaders.  But these are just a few good candidates!  Many other plants may do as well or better than the ones suggested here and you know the little microclimate next to your house better than anyone.  We encourage you to explore your options with the easy-to-use combination search in our Native Plant Information Database.  You'll want to select 'Texas' for the state, and 'Herb' for the Habit because your space is narrow, then choose the proper light and water conditions.  You can also choose to search by bloom time and color.

We would be remiss not to mention that warning bells clanged in our head upon reading the words "next to our house" and "holds a lot of water."  Standing water next to your foundation (especially in the highly expandable clay soils so common in Dallas) is bad news.  We hope that the wet strip next to your house is actually a few feet away from the foundation rather than right up against it.  If it's the latter, you would do better to address your drainage issue by adding soil next to the foundation so that water can drain away from it or consulting with a drainage expert if the problem is more complicated.  Additionally, it's generally not a good idea to have vegetation right up against the house, especially if you have wood siding that could rot.  It is much better to have a clear path with rocks or low groundcover (at least 1 foot wide) all the way around the house for good air circulation, easy access for maintenance, and to discourage insects and rodents.  Either way, you have a number of options!

Packera obovata

Chasmanthium latifolium

Physostegia virginiana