Dwarf Crested Iris (Iris cristata) 2015-5-9 www9 Patuxent Research Refuge, Anne Arundel County, MD

a wild native - grows only a few inches tall
endangered in Maryland
http://www.fs.fed.us/wildflowers/beauty/iris/Dwarf_Woodland/images/iris_cristata_tgb2_lg.jpg

There is a similar dwarf, Iris verna. Where cristata has the raised "crest", verna has a flat orange patch. see:
https://commons.wikimedia.org/wiki/File:Iris_verna,_Dwarf_Iris.jpg