Dwarf palmetto with copper canyon daisy in dappled-to-full shade. (Bee Caves in winter)
Sparkler sedge is good for brightening shade but it requires a fair amount of water — maybe try one or two? (Zilker Botanical Garden in spring)
White mistflower / Shrubby boneset / Fragrant mistflower is an excellent butterfly plant for part shade. Blooms in fall and usually stays evergreen. (Barton Hills in fall)
Variegated gingers with aspidistra ‘milky way’ and sedges (Onion Creek in spring)
Holly fern looks great under live oaks, especially near boulders. (South Austin in fall)
Nolina texana - a weeping succulent with thin leaves and white blooms - can take deep shade
Sedges in shade (Barton Springs Nursery, fall)
Aspidistras paired with variegated ginger (background), liriope, blue shade ruellia, and holly fern. (San Antonio Southwest School of Art, summer)