When to plant perennial ryegrass

Perennial Ryegrass planting dates by zone

Spring dates before the last frost assume the soil has thawed and is dry enough to work. After a late or wet spring, wait for that even if the date has passed.

Where frost is rare

In the South and Southwest, perennial ryegrass is mainly sown in fall over dormant bermudagrass to keep the lawn green through winter, then it dies back as the bermudagrass resumes growth. Sow when days have cooled (low-to-mid 70s F in Florida; about 80-85F days and 55F nights in Arizona's low desert). Sowing too early favors the bermudagrass, while sowing too late risks frost damage to seedlings. Clemson says overseeding home lawns is generally not recommended and, if done, should be limited to bermudagrass; Arizona says St. Augustinegrass and zoysiagrass are generally not suited to overseeding. Frost-free south Florida lawns usually stay green, so overseeding is not needed there. In spring, lower the mowing height and mow more often to help the bermudagrass take back over.

Based on UF/IFAS EDIS ENH14 'Overseeding Florida Lawns for Winter Color' (North Florida Oct-early Nov; Central Florida Oct to mid-Nov/early Dec; south Florida usually not needed); University of Arizona AZ1683 (October in the low desert); Texas A&M AgriLife Bexar County (late Oct-Nov, 'after the first frost'); Clemson HGIC 1206 (about 30 days before first frost). Zone keys are our approximate match of these regions (zone_9 = north/central Florida, Arizona low desert, south Texas; zone_10 = central/south Florida); the sources give regions, not USDA zones. Warm-winter areas are matched to zones approximately, so use the months for your region.