As summer winds down in California, your lawn faces unique challenges that can make or break its health heading into fall. The combination of intense heat, water restrictions, and changing daylight patterns creates a tricky balancing act for homeowners.
Avoiding these common late-summer lawn blunders will save you headaches and money while keeping your yard looking its best.
1. Panic-Cutting Before A Heat Wave
Giving your lawn a super-short trim before scorching temperatures arrive might seem logical, but it’s actually lawn suicide. Short grass exposes soil to direct sunlight, increasing water evaporation and stress.
The roots become vulnerable without adequate shade from longer blades. Instead, keep your grass at 3-4 inches tall during late summer to provide natural cooling and moisture retention. This height creates a mini-ecosystem that protects against the worst of California’s August and September heat.
2. Watering At High Noon
Sprinkling your lawn during the hottest part of the day is like throwing money at the sun. Water evaporates rapidly between 10am and 4pm, especially during late summer when temperatures soar past 90 degrees in many California regions.
Droplets can even act as tiny magnifying glasses, potentially scorching grass blades. Schedule irrigation for early morning (before 8am) when winds are calm and temperatures are cooler. Your lawn will absorb more moisture, and you’ll waste less water during drought-prone months.
3. Fertilizing With Heavy Nitrogen
Dumping high-nitrogen fertilizer on your lawn in late summer can trigger a growth spurt at exactly the wrong time. Your grass will produce tender new blades that can’t handle the stress of lingering heat waves.
Plus, excess nitrogen often runs off during irrigation, polluting local waterways. Hold off on heavy feeding until temperatures consistently cool down. If your lawn looks hungry, apply only a light, slow-release fertilizer specifically formulated for summer stress recovery.
4. Ignoring Drought Stress Signs
Footprints that stay visible long after walking across your lawn are crying out for help! This classic drought stress indicator appears when grass blades lose their resilience due to insufficient moisture.
Other warning signs include blue-gray coloring and folded or rolled blades. Don’t wait until your entire lawn turns brown to take action. Perform the screwdriver test – if you can’t easily push a screwdriver into the soil, your lawn needs a deep, thorough watering despite water restrictions.
5. Overseeding With Cool-Season Grasses Too Early
Eager homeowners often jump the gun on fall overseeding while temperatures still regularly hit the 90s. Cool-season grass seeds like fescue and ryegrass simply can’t establish properly when soil temperatures remain above 75°F.
The young seedlings waste energy trying to survive rather than developing strong root systems. Wait until nighttime temperatures consistently drop below 65°F before overseeding. For most California regions, this means late September or even October, not August or early September.
6. Letting Thatch Build Up
That spongy layer between your grass and soil might seem harmless, but excessive thatch becomes a summer nightmare. Once thatch exceeds ½ inch thickness, it prevents water from reaching roots and creates a perfect breeding ground for pests and diseases.
Late summer is actually an ideal time to dethatch warm-season California lawns like Bermuda and St. Augustine. Rent a power rake or vertical mower to remove this barrier, allowing your lawn to breathe again before fall arrives.
7. Applying Weed Killers During Heat
Spraying herbicides when temperatures exceed 85°F can backfire dramatically. Most weed killers become volatile in high heat, potentially drifting onto and damaging desirable plants and even your neighbor’s prized roses.
Heat-stressed grass is also more susceptible to herbicide damage. Save your weed control efforts for cooler fall days. If weeds are truly out of control in late summer, spot-treat individual weeds by hand during the coolest part of the morning rather than broadcast spraying.
8. Forgetting To Adjust Sprinkler Timing
Running the same irrigation schedule from early to late summer is a rookie mistake. As days gradually shorten after the solstice, your lawn’s water needs change significantly. Many controllers still dutifully water at June levels when September requirements are quite different.
Factor in seasonal water restrictions too! Reassess your lawn’s needs by checking soil moisture weekly. Most California lawns need about 20% less water in September than they did in July, even with similar temperatures.
9. Neglecting Equipment Maintenance
By late summer, your mower blade has likely gone dull after months of weekly cutting. Dull blades tear grass rather than cleanly cutting it, creating ragged edges that lose more moisture and are more susceptible to disease.
The brutal combination of heat stress and poor cuts can devastate your lawn. Take an hour to sharpen your mower blade or replace it entirely. While you’re at it, clean the mower deck of caked-on grass that harbors fungi and bacteria waiting to infect your lawn.