June Lawn Care Jacksonville FL: Surviving Peak Summer Heat

Welcome to summer in Jacksonville. If you're new here, buckle up—June is when our lawns face serious heat stress. We're talking 90+ degree days, afternoon thunderstorms that flood your yard for twenty minutes then disappear, and humidity that makes you question every life decision that brought you to Florida.

But here's the thing: your lawn can absolutely thrive in June if you know what you're doing. I've been managing lawns from Neptune Beach to World Golf Village through countless brutal summers, and the yards that look great in June are the ones where owners adjusted their approach for summer survival mode.

Let me show you how.

June Weather Reality Check

By June, we're solidly in summer. Average highs around 90°F, lows in the mid-70s, and humidity that hovers around 75%. Your grass is growing fast, but it's also stressed.

Soil temperatures are in the 80s, which is actually great for our warm-season grasses—they love it. But it also means pests are thriving, disease pressure is real, and water evaporates faster than you can say "St. Augustine decline."

We typically get 5-7 inches of rain in June, mostly from afternoon thunderstorms. Sounds like a lot, right? But it's inconsistent. You might get 2 inches in one storm, then nothing for a week. Your irrigation game needs to be tight.

Mowing: The Most Important Thing You'll Do

In June, mowing strategy matters more than any other month. Mess this up and your lawn will suffer.

Height is Critical

Raise your mower deck. Seriously. Taller grass means:

• More leaf surface for photosynthesis
• Deeper shade on soil (keeps roots cooler)
• Better moisture retention
• Stronger competition against weeds

Recommended heights:

• St. Augustine: 4 to 4.5 inches (yes, taller than spring)
• Zoysia: 2.5 to 3 inches
• Bahia: 4 to 5 inches

I know, it looks shaggier. Your neighbors in Deerwood with their country club aspirations might side-eye you. But tall grass survives summer. Scalped grass burns out.

Frequency

You're probably mowing twice a week now. With our June rain and heat, grass grows fast. The one-third rule still applies—never remove more than one-third of the blade height in a single mowing.

If you're going on vacation, hire someone or have a neighbor help. Letting your lawn get overgrown then scalping it when you return is one of the worst things you can do.

Blade Sharpness

Dull blades tear grass instead of cutting it clean. Those tears turn brown in the sun and create entry points for disease. If you're mowing twice a week all month, sharpen blades every two weeks or you'll see the difference in lawn quality.

Leave the Clippings

Unless you're cutting way too much at once, leave the clippings. They return nitrogen to the soil and act as a light mulch layer. In June, that's free fertilizer and moisture retention. Just make sure they're not so thick they smother the grass underneath.

Watering: The Make-or-Break Factor

June watering is where most people go wrong. Too much, too little, wrong time of day—it all matters.

How Much

Your lawn needs 1 to 1.5 inches of water per week. That includes rainfall. Put out rain gauges or tuna cans around your yard and measure what you're actually getting.

During a rainy week? You might not need to irrigate at all. During a dry week? You'll need to supplement.

When to Water

Early morning, ideally between 4 and 8 AM. Why?

• Grass blades dry before evening (reduces fungus risk)
• Less water loss to evaporation
• Winds are typically calmer
• You're using water when grass can actually absorb it

Watering in the afternoon is wasteful—half of it evaporates. Watering in the evening keeps grass wet overnight, which invites disease.

How Often

Deep and infrequent beats shallow and frequent every time. Two to three times per week, applied slowly enough to soak in rather than run off, builds deep roots that handle stress better.

Daily light watering creates shallow roots that fry when conditions get tough. I see this all the time in newer neighborhoods like Nocatee where automated systems are set to water every day. Stop it.

Sandy Soil Challenges

Our Jacksonville soil drains fast. That's good for preventing standing water, bad for holding moisture. Water slowly—if you see runoff, you're applying too fast. Run your zones multiple times with soak time in between if needed.

Fertilization: Less is More

June is not the time for heavy fertilization. You already fed in March and May. Too much nitrogen in summer creates excessive growth that requires more mowing, more water, and more stress on the plant.

If you're on a fertilizer program, you might do a very light application (0.5 pounds nitrogen per 1,000 square feet) in June, but it's not required. Many successful lawns skip June fertilization entirely.

What IS helpful: micronutrients. Iron in particular can green up St. Augustine without forcing growth. If your lawn looks yellowish (chlorotic), iron might be the answer.

Apply iron on a day when it won't rain for 24 hours—it can stain concrete badly. Ask me how I know. Better yet, just sweep driveways and sidewalks immediately after application.

Pest Management: June is Prime Time

The heat brings pests out in force. Two major ones to watch:

Chinch Bugs

These are public enemy number one for St. Augustine in June. They suck juice from grass blades, causing yellow patches that turn brown and die. Check sunny areas along driveways and sidewalks in Mandarin, Southside, or anywhere else with lots of St. Augustine.

How to check: Part the grass at the edge of a damaged area. Look for tiny black bugs with white X-shaped wings. You might also see nymphs (smaller, reddish).

If you find them, treat immediately with an appropriate insecticide. Products with bifenthrin or lambda-cyhalothrin work well. Treat the affected area plus a buffer zone.

One application usually isn't enough—chinch bugs are tough. Follow up in two weeks.

Mole Crickets

These tunnel through sandy soil eating roots and shoots. You'll see raised tunnels, especially in lawns with Bahia grass in Arlington or Westside.

They're most active at night. Do a soap flush test (dish soap mixed with water, poured over suspected area) and they'll surface if present.

Treat with products containing bifenthrin or imidacloprid. Early morning or evening applications work best when they're active.

Grubs

White grubs (beetle larvae) feed on roots underground. Affected areas feel spongy and grass pulls up easily. Armadillos and moles tearing up your lawn? They're following grubs.

Treat with products containing imidacloprid or clothianidin. Water it in thoroughly—grubs live in the root zone.

Disease Management: Gray Leaf Spot

This is the big one for June. Gray leaf spot loves St. Augustine in hot, humid, wet conditions (which is every June in Jacksonville).

Symptoms:

• Gray or tan lesions on grass blades
• Lesions elongate and develop dark borders
• Severely affected areas look scorched

Prevention:

• Avoid late-day watering
• Don't over-fertilize (soft, lush growth is susceptible)
• Improve air circulation
• Mow regularly (don't let grass get too tall)
• Water early morning only

Treatment: If you catch it early, adjusting cultural practices might be enough. For severe outbreaks, fungicides with azoxystrobin or propiconazole work. Follow label rates and timing.

Honestly, prevention is way easier than cure with gray leaf spot.

Weed Control: Stay on Top of It

You should have less weed pressure in June if you did your pre-emergent work in spring. But weeds still happen:

Spurge (both spotted and prostrate): Super common in June. Spot-treat with post-emergent broadleaf herbicide. These spread fast, so catch them early.

Crabgrass (if your pre-emergent failed): Post-emergent products work but they're tough on your lawn in heat. Spot-treat carefully.

Sedges: Still around, still annoying. Use sedge-specific products.

Important: Read labels carefully. Many herbicides shouldn't be applied when temperatures exceed 85-90°F. In June, that means early morning application before 9 AM.

Also, herbicides stress grass. If your lawn is already stressed from heat, you might do more harm than good. Hand-pull if possible.

Irrigation System Maintenance

June rain is hard on irrigation systems. After big storms, walk your system:

• Check for broken or clogged heads
• Look for leaks
• Verify spray patterns
• Make sure zones are running correct duration
• Test your rain sensor (most don't work)

A broken head shooting water onto the sidewalk all night wastes hundreds of gallons. Fix it immediately.

Dealing with Afternoon Storms

June thunderstorms dump a lot of water fast. If you have low spots that puddle (common in Riverside and Mandarin where the land is flatter), you've got issues.

Standing water for more than a day invites disease and kills grass roots. Options:

• Improve drainage with French drains or catch basins
• Regrade problem areas
• Aerate to improve water infiltration
• Plant water-tolerant varieties in problem zones

This is a bigger project, but June will expose drainage problems clearly.

Shade Management

Your big oaks are fully leafed out. That's great for keeping your house cool, tough for grass underneath.

In deep shade areas around San Marco or Riverside:

• Increase mowing height even more (4.5+ inches for St. Augustine)
• Reduce watering (shade means less transpiration)
• Reduce or skip fertilizer (shade grass grows slower)
• Prune lower branches to allow filtered light

St. Augustine is shade-tolerant compared to other grasses, but even it has limits. In deep, dense shade, consider shade-loving groundcovers like Asiatic jasmine instead of fighting for grass.

Landscape Bed Maintenance

Mulch breaks down fast in our heat and humidity. June is a good time to refresh beds:

• Add 1-2 inches of fresh mulch
• Pull weeds before they set seed
• Trim back aggressive growers
• Water shrubs deeply during dry spells

Keeping beds looking good makes your lawn look better too. It's all part of the package.

June Lawn Care Schedule

Early June:

• Raise mower height
• Adjust irrigation for summer schedule
• Apply iron if needed
• Scout for chinch bugs

Mid-June:

• Continue regular mowing (twice weekly)
• Monitor for gray leaf spot
• Treat pests if found
• Hand-pull weeds in heat of day to avoid herbicide stress

Late June:

• Check irrigation system after storms
• Sharpen mower blades again
• Assess any problem areas
• Plan for July adjustments

All Month:

• Water early morning only
• Measure actual water application
• Leave clippings when mowing
• Stay vigilant for pests and disease

What NOT to Do in June

Avoid these common mistakes:

• Don't scalp your lawn
• Don't apply herbicides in the heat of the day
• Don't let grass go dormant unnecessarily
• Don't ignore chinch bug damage (it spreads fast)
• Don't water in the evening
• Don't over-fertilize
• Don't let equipment maintenance slide

The Brutal Truth About June

Not every lawn makes it through June looking great. Some years are tougher than others. If we get a drought, or pest pressure is high, or you inherited a lawn with poor soil and weak grass, you might have some struggles.

That's okay. The goal isn't perfection—it's survival and steady improvement. Fix problems as you find them, learn what works for your specific yard, and build on that knowledge each year.

The best lawns in Ponte Vedra Beach and Sawgrass didn't get that way in one season. They're the result of years of consistent care, adjusted for conditions, focused on plant health over cosmetics.

Looking Ahead to July

If you nail June, July is just more of the same. You've got your watering dialed in, mowing routine established, pests under control. Keep doing what works.

But if June exposed problems—poor drainage, pest damage, weak areas—use the knowledge to fix things. Maybe that's a renovation project in fall, or adjusting your maintenance routine, or calling in professional help for the next season.

Every June teaches you something about your lawn. Pay attention, take notes, and get smarter about your specific yard every year.

Keep Perspective

Jacksonville summers are tough on lawns. But St. Augustine, Zoysia, and Bahia evolved for exactly these conditions. Give them the basics—adequate water, proper mowing, pest control when needed—and they'll perform.

Walk around your neighborhood. The best lawns aren't the ones getting the most inputs. They're the ones getting the RIGHT inputs at the right times, with realistic expectations for what grass can do in 95-degree heat with 80% humidity.

You've got this. Dial in your routine, stay consistent, and your lawn will make it through June looking good. Maybe not country club perfect, but healthy, green, and improving. That's the real win.