Here is a plant that people either love or hate. It's a pretty ground cover called Mexican Evening Primrose, Oenothera speciosa(pronounced EE-noth-er-a). It grows less than 1 foot tall and spreads by seed. This full sun lover blooms here in spring and summer and looks really crappy in winter. If it reseeds where you don't want it then it could be considered a weed. But it's so pretty now!