What is xeric mulch vs organic mulch?
Xeric mulch (decomposed granite, rubber) and organic mulch (hardwood, cedar) are ground coverings that retain soil moisture and regulate temperature, but differ in composition and durability for Central Texas gardens.
Mulch in Austin beds falls into two main categories based on composition and performance. Organic mulch breaks down over time and includes hardwood chips, cedar, and shredded bark. These materials improve soil structure as they decompose, add some nutrients, and provide a finished look. However, they require periodic replenishment in the Texas heat, typically yearly or every other year, since decomposition accelerates in hot, dry conditions.
Xeric mulch resists decomposition and includes decomposed granite (DG), gravel, and rubber chips. These inorganic materials last longer in Austin's sun and heat without breaking down, making them durable ground covers that suppress weeds and retain soil moisture. Decomposed granite is popular across the region for its natural appearance and permeability, while rubber mulch offers dark color retention in full-sun beds.
Both types regulate soil temperature and reduce water needs by shielding soil from direct sun. The choice depends on your goals: organic mulch suits beds where you want annual soil enrichment and don't mind regular top-ups, while xeric mulch works for established plantings, hot exposures, and homeowners who prefer minimal maintenance. Many Austin landscapes use both in different zones.
Local landscape professionals can recommend the right mulch type for your specific beds and water goals.