What Makes a Grass “Heat-Tolerant”?
Grasses are generally grouped into two broad categories: warm-season and cool-season. Warm-season grasses evolved in tropical and subtropical regions, so they tend to grow most actively when soil and air temperatures are high, and they generally handle intense sun and sustained heat better than cool-season species. Cool-season grasses, which trace back largely to Europe, tend to grow best in spring and fall and often slow down or struggle once summer heat sets in.
That distinction matters because the “best” grass for a hot climate usually isn’t about finding one single miracle variety — it’s about matching a grass’s natural growth pattern, root depth, and water needs to your specific heat, humidity, soil, and sunlight conditions.
Best Warm-Season Grasses for Hot Climates
These are the warm-season grasses most commonly recommended for hot regions, based on how they’re generally described across lawn-care and extension resources.
Bermudagrass
Bermudagrass is frequently cited as one of the most heat-tolerant lawn grasses available, with an optimal growth range often described as roughly 95–100°F. It tends to grow quickly, spreads aggressively via above- and below-ground stems, and generally recovers well from wear, which is part of why it shows up often on sports fields and golf fairways in southern climates. It typically needs full sun to perform well and tends to go dormant (turning brown) once temperatures drop, usually below around 65°F — see our guide to dormant grass for what that looks like and how to tell it apart from a dead lawn.
The tradeoff is maintenance: Bermuda’s fast growth often means mowing it more frequently than slower-growing options, along with more regular fertilization during peak summer growth.
Zoysiagrass
Zoysia is another warm-season option generally considered highly heat-tolerant, though it tends to grow more slowly than Bermuda. It’s often described as forming a denser, softer turf, and it generally handles some light shade better than Bermuda does. Because of its slower growth, Zoysia typically needs less frequent mowing, though thatch buildup can become an issue over time, particularly on fertilized lawns.
St. Augustinegrass
St. Augustinegrass is commonly recommended for hot, humid, and coastal regions. It’s often described as having a wider leaf blade and generally better shade tolerance than Bermuda, which can make it a reasonable option for lawns that get a mix of sun and shade in warm, humid climates.
Buffalograss
Buffalograss is a native prairie grass often highlighted as one of the lowest-water turf options. It generally needs comparatively little mowing and little irrigation once established, which makes it a candidate for drier, low-maintenance hot-climate lawns. It tends to be less tolerant of heavy foot traffic than Bermuda or Zoysia, so it may suit lower-use areas better than high-traffic yards. For readers specifically in California, our guide to low-water, drought-tolerant grass for California covers a California-bred buffalograss variety in more detail.
Bahiagrass
Bahiagrass is generally described as tolerant of poor, sandy soil and high humidity, which is part of why it’s common in parts of the hot, humid Southeast. It tends to develop fairly deep roots, which can help with moisture capture, though it’s often considered a rougher-textured, less refined-looking turf than Bermuda or Zoysia, and it can produce seed heads relatively quickly after mowing.
Centipedegrass
Centipedegrass is typically described as the slowest-growing of the common warm-season lawn grasses, with comparatively low fertilizer needs. That slower growth generally translates into less frequent mowing, but centipede tends to have shallower roots than Bermuda, which can leave it more vulnerable during extended dry periods without supplemental water, and it’s generally considered more susceptible to winter injury than other warm-season grasses because it doesn’t have a strong true dormant period.
What About Cool-Season Grasses in Heat? (Tall Fescue and Its Downsides)
Among cool-season grasses, tall fescue is often described as the most heat-tolerant option, generally because it can develop deeper roots than many other cool-season species, which can help it access moisture during dry, hot stretches. That said, tall fescue is still a cool-season grass at its core, so it generally doesn’t match the heat tolerance of true warm-season species like Bermuda or Zoysia in sustained extreme heat.
Some commonly cited downsides of fescue in hot weather include a tendency to thin out or go somewhat dormant-looking under prolonged heat and drought stress, and generally higher water needs during summer compared with warm-season grasses that are actively growing in that heat. Fescue tends to be a more reasonable fit for transition-zone climates — areas where summer heat is real but not as extreme or prolonged as in the Deep South or desert Southwest — rather than for the hottest regions. For a closer side-by-side look at this tradeoff, see our comparison of tall fescue vs. Bermuda grass.
Will Grass Grow in 90°F (or Hotter) Heat?
Generally, yes — warm-season grasses are typically described as actively growing in 90°F weather, and many sources cite Bermudagrass specifically as having an optimal growth range around 95–100°F. Cool-season grasses tend to respond differently: they often slow their growth and may show heat stress as temperatures climb well into the 90s, particularly if moisture is also limited.
In other words, whether grass “grows” in 90-degree heat depends heavily on which type of grass you have and how much water and sun it’s getting, rather than there being one universal answer.
What Is “Poor Man’s Grass”?
The term “poor man’s grass” doesn’t have one single, universally agreed-upon meaning, and it’s used somewhat loosely in casual lawn-care conversation. In some usage it refers to common Bermudagrass (as opposed to improved or hybrid cultivars) because it’s inexpensive, spreads on its own, and tolerates neglect reasonably well. In other usage, it’s applied more broadly to whatever tough, low-input grass or ground cover fills in a yard without much deliberate care or expense. Because the term is used inconsistently, it’s worth treating as informal shorthand rather than a specific botanical variety.
How to Keep Grass Green in 100°F Weather
Mowing Height in Hot Weather
A commonly cited general guideline is to mow slightly higher during hot weather and to avoid removing more than about one-third of the grass blade in any single mowing. Taller grass blades generally help shade the soil surface, which can keep roots somewhat cooler and reduce moisture loss. This is a reasonable argument for letting grass run a bit longer than usual during the hottest stretches of summer, though “longer” still generally means staying within the recommended mowing height range for your specific grass type rather than letting it grow unchecked.
Watering Guidance — Is It Okay to Water in 100°F Heat?
Watering lawns during 100°F weather is generally considered fine and often advisable for actively growing grass, but timing matters. Watering early in the morning is commonly recommended over midday or evening watering, generally because morning watering reduces evaporation loss (compared with midday heat) and gives grass blades time to dry out during the day (compared with evening watering, which can leave grass damp overnight and potentially more prone to fungal issues).
Most lawn grasses are generally described as needing roughly 1 inch of water per week from rainfall or irrigation, and during extended dry, hot periods even fairly drought-tolerant grasses like Bermuda or Zoysia may need somewhat more to stay green and actively growing. Deep, less frequent watering is typically favored over frequent light watering, since it tends to encourage deeper rooting, which in turn generally supports better heat and drought tolerance over time.
Choosing the Best Grass for Your Region (Including Texas Heat)
For hot, sunny regions like much of Texas, Bermudagrass is frequently the grass most commonly recommended, generally because of its heat tolerance, drought resilience once established, and ability to recover from heavy use. Zoysia is often mentioned as an alternative where a denser, softer-textured lawn is preferred and slightly slower growth (and therefore less mowing) is acceptable. In humid coastal areas, St. Augustinegrass is more commonly recommended, while sandy or lower-fertility soils in parts of the hot Southeast often favor Bahiagrass or centipedegrass.
Soil type, sun exposure, humidity, typical rainfall, and how much foot traffic the lawn needs to handle all generally factor into which grass makes sense for a specific property — there generally isn’t a single “best” grass that applies everywhere. If water availability is the biggest constraint in your area, our drought-tolerant grass guide for California and our no-mow, low-maintenance grass guide go deeper into lower-input options.
FAQ
Will grass grow in 90-degree heat? Generally, yes, for warm-season grasses like Bermuda, Zoysia, and St. Augustine, which are typically described as actively growing in that temperature range. Cool-season grasses tend to slow down or show stress at that point, especially with limited water.
What is poor man’s grass? The term is used informally and inconsistently — often referring to common (non-hybrid) Bermudagrass, and sometimes more loosely to any tough, low-cost grass or ground cover that fills in a yard with minimal care.
How do I keep my grass green in 100-degree weather? Commonly cited steps include mowing slightly higher (without removing more than about a third of the blade at once), watering deeply but less frequently, and watering in the early morning rather than midday or evening.
Is it okay to water my grass in 100-degree heat? Generally yes for actively growing grass, with early-morning watering typically recommended over midday or evening watering.
What type of grass is best for growing in the summer? Warm-season grasses such as Bermuda, Zoysia, St. Augustine, Buffalograss, Bahiagrass, and centipedegrass are generally the ones most associated with strong summer growth, since that’s their natural active-growing season.
What are the downsides of fescue grass? Tall fescue can thin out or show stress under prolonged heat and drought, and it generally needs more water during hot summer stretches compared with actively growing warm-season grasses.
Is it better to let grass grow long in hot weather? Letting grass run slightly taller than usual during hot weather is a commonly cited practice, since taller blades can help shade the soil and roots — but this generally means staying within the recommended mowing-height range for the grass type, not letting it grow unchecked.
What type of grass is best for Texas heat? Bermudagrass is the variety most commonly recommended for hot, sunny Texas conditions, with Zoysia as a common alternative for a denser, softer lawn, and St. Augustine more common in humid coastal parts of the state.