Ask Mr. Smarty Plants

From the presence of large pecan trees Mr. Smarty Plants guesses that you live in a Blackland Prairie site with soil that can retain moisture.  Although many fragrance-producing plants in your area are not natives, there are natives that can fill that role very well.  The examples I shall mention should all thrive in light shade of the type usually found under large pecan trees.  The more light, the better blooms you can expect.  For early spring, before your pecan trees leaf out, try Viola blanda var. palustriformis (Sweet white violet),  Prunus mexicana (Mexican plum) and Sophora secundiflora (Texas mountain laurel)(fragrance from this latter plant can be overwhelming, so place it a few feet away from "nose-zero"). Clethra alnifolia (Coastal sweet pepperbush), Lindera benzoin (Northern spicebush),Phlox pilosa (Downy phlox),Philadelphus texensis (Texas mock orange), Achillea millefolium (Common yarrow), Eysenhardtia texana (Texas kidneywood), and Ageratina havanensis (Havana snakeroot), locally called White Mistflower, are worth considering.  Fall-blooming species include Hamamelis virginiana (Witch hazel) and Tagetes lemmonii (Copper canyon daisy).  Foliage of the latter species, when brushed against, releases a powerful aroma attractive to some people but not to others.  Additional selections that release their fragrance when brushed against include Rhus aromatica (Fragrant sumac) and Mentha arvensis (Wild mint).  Click on the underlined species names to determine if each appears suitable for your setting on the basis of light and moisture requirements.

You should be able to locate most of these plants at one of your local native plant nurseries.