Zone 9 and 10 conditions
Zone 9 has average winter lows of about 20°F to 30°F, and zone 10 about 30°F to 40°F. Winter cold is rarely a problem for grasses in these zones. Instead, the main issues are long, hot summers, sometimes high humidity, and in some regions sandy soil or salt spray.
The result is that many grasses that thrive in cooler climates do not do their best here, while grasses that need heat perform very well. Your exact conditions vary widely: zones 9 and 10 include dry inland areas, humid coastal areas and Mediterranean-type climates, so match the grass to your local rainfall. For Florida specifically, see our article on grasses for Florida landscapes; for the West Coast, see grasses for the Pacific Northwest.
Heat-loving picks
Tall grasses
- Pink muhly grass (Muhlenbergia capillaris): a native with a cloud of pink to purple plumes in fall. It is heat and drought tolerant and does well in full sun and well-drained soil. It is typically listed for zones 6 to 9 or 10. See how to grow pink muhly grass.
- Bamboo muhly (Muhlenbergia dumosa): fine, feathery and weeping, reaching about 5 to 7 feet. It enjoys heat and is often used where a bamboo look is wanted without the spread of running bamboo. See grasses that look like bamboo.
- Fakahatchee grass (Tripsacum dactyloides): a bold, tropical-looking native about 5 to 6 feet tall and wide, with arching leaves. It tolerates sun to part shade, though it prefers moisture and is not salt tolerant.
- Pampas grass (Cortaderia selloana): large white plumes, typically listed for zones 7 to 10. Vigorous and fast-growing, with sharp leaf edges. It is considered invasive in some warm regions, particularly in parts of California, so check local guidance before planting. See is pampas grass invasive.
- Maiden grass (Miscanthus sinensis): hardy through zone 9 in most listings. It handles heat well when watered, but may reseed in some regions.
Medium grasses
- Little bluestem (Schizachyrium scoparium): listed for a broad range of zones, and fine in heat if soil is well drained.
- Blue grama and Elliott’s lovegrass (Eragrostis elliottii): drought-tolerant, with blue-gray foliage in Elliott’s lovegrass.
- ‘Hameln’ fountain grass (Pennisetum alopecuroides): hardy to zone 9 and handles heat when watered.
- Lomandra (Lomandra longifolia and compact cultivars): an Australian, grass-like perennial that tolerates heat, and many cultivars are used in warm-climate landscapes.
Short and grass-like plants
- Sedges (Carex): many are rated for zones up to 9 or 10, and they suit part shade. Real Simple lists sedge as hardy from zone 3 to zone 10, but performance in intense heat varies by species.
- Liriope (Liriope muscari ‘Big Blue’ and similar): a tough, grass-like groundcover for sun to shade, valued in hot zones.
- Mondo grass (Ophiopogon): a shade groundcover that likes some moisture. See liriope vs mondo grass.
- Blue fescue: usually does less well in hot, humid summers, so treat it as a short-lived plant at best.
Grasses that struggle in heat
Cool-season grasses such as blue fescue, blue oat grass, feather reed grass and tufted hair grass can decline in long, hot, humid summers, particularly in the warmest parts of zones 9 and 10. Japanese forest grass needs shade and moisture, and does best where summers are cool. If you want to try them, give them afternoon shade and good drainage.
Invasive cautions
Warm climates favor self-seeding. A few cautions:
- Mexican feather grass self-seeds heavily and is flagged in some regions.
- Purple or red fountain grass (Pennisetum setaceum) is invasive in some warm regions. It is popular in nurseries but can spread into wild areas, so look for sterile cultivars and check local lists.
- Pampas grass is a problem in some places, as above.
- Japanese blood grass is related to cogon grass, a serious weed in the Southeast, and some sources advise avoiding it in that region.
- Running bamboos are far more vigorous than most grasses, and clumping types are the safer choice. See running vs clumping bamboo.
Your local extension office or native plant society can give a current list of grasses to avoid.
Planting and watering
Plant in fall or spring when temperatures are moderate, and keep young plants watered through their first summer. In most zone 9 and 10 climates, fall planting gives roots time to establish before the heat. Once established, many of the grasses above are quite drought tolerant. Mulch to hold moisture and suppress weeds, and avoid heavy fertilizer, which makes tall grasses flop.
Cutting back in mild winters
In mild climates, grasses may not go fully dormant. Many growers cut back deciduous grasses in late winter or early spring, before new growth, to renew the foliage. Evergreen types need only dead leaves and old flower stalks removed. If you have moved from a colder zone, our guide to zones 7 and 8 shows how the same plants behave in somewhat cooler conditions.