These unthirsty succulents, flowers, and grasses will thrive with little care - even on a roof.
1. Echinocactus grusoni
Golden spines cover this slow-growing native Mexican cactus that reaches 4 feet tall and 2½ feet wide. Small yellow flowers top the plant in summer. Sunset climate zones 12-24.
2. Lewisia cotyledon 'Sunset Strain'
This bloomer, from California and Oregon, has evergreen foliage and reaches a foot high and 10 inches wide. It's great in rock gardens, but needs excellent drainage. Zones 1-7 and 14-17.
3. Nassella tenuissima
Wispy green blades form clumps reaching 2 feet tall and wide. This grass found in Texas, New Mexico, and Mexico develops blond summer flower heads. Zones 2b-24.
4. Sedum spathulifolium 'Cape Blanco'
Tiny blue-green leaves form tight rosettes on trailing stems. This low grower from California makes a great groundcover. Zones 2-9 andRead More »from 12 Great Low-water Plants