March Lawn Care Jacksonville FL: Spring Green-Up Season

March is when Jacksonville lawns wake up for real. If February was the warm-up act, March is showtime. I've been working on lawns from Southside to Amelia Island for over a decade, and this month is when everything kicks into gear. Your St. Augustine starts pushing out new runners, Zoysia begins to green up, and honestly, the weeds think it's their time to shine too.

The good news? If you stayed patient in February, you're about to see why. Let me break down exactly what needs to happen this month.

March Weather: The Sweet Spot

We're looking at daytime temperatures in the 70s, nighttime temps in the 50s, and soil temperatures finally hitting that magic 65-70°F range. This is the temperature where grass roots get active and start taking up nutrients.

You'll notice it driving down San Jose Boulevard or Atlantic Boulevard—lawns suddenly look alive again. That's not magic, it's biology responding to warmth and longer days.

We usually get about 3-4 inches of rain in March, which is decent but not always consistent. Some years it's dry, some years we get soaked. Either way, you'll need to pay attention to moisture levels.

Fertilization: Finally, It's Time

This is the month everyone's been waiting for. Your first fertilizer application of the year should happen in March, but timing matters.

Wait until you see active growth. What does that mean? Your grass should be greening up and you should have mowed at least twice. Don't jump the gun just because it's March 1st. If we had a late cold snap, you might wait until late March.

What to Apply

For St. Augustine (most of us from Riverside to Nocatee), you want a fertilizer with a 3-1-2 or 4-1-2 ratio. Something like 15-5-10 or 16-4-8 works great. You want nitrogen for green-up, but not so much that you're forcing excessive growth you can't keep up with.

Apply at the rate of 1 pound of nitrogen per 1,000 square feet. Don't guess—measure your lawn. I see people over-apply all the time, especially in neighborhoods like Baymeadows where everyone's competing for the greenest lawn. More is NOT better. You'll just burn the grass, waste money, and send excess nutrients into our waterways.

Slow-Release vs. Quick-Release

Slow-release nitrogen is your friend. It feeds the grass over 8-10 weeks instead of all at once, giving you consistent growth without the crazy surge-and-crash of quick-release fertilizers.

Quick-release makes your lawn look amazing for two weeks, then you're mowing three times a week and dealing with thatch buildup. Save yourself the headache.

Application Tips

• Use a broadcast spreader for even coverage
• Apply when grass is dry but water it in within 24 hours
• Don't apply before heavy rain (you'll just wash it away)
• Avoid getting fertilizer on driveways and sidewalks—sweep it back onto the lawn
• Keep pets and kids off until after you've watered it in

Mowing: Now We're Talking

March is when mowing becomes a regular thing again. You're probably looking at once a week by mid-month, possibly twice a week by the end if we get warm and wet.

Height matters:

• St. Augustine: 3.5 to 4 inches
• Zoysia: 2 to 2.5 inches
• Bahia: 3 to 4 inches

Never cut more than one-third of the blade height at once. If you let it get too tall, take it down gradually over multiple mowings. Scalping it in one go stresses the grass and opens the door for weeds and disease.

Mowing Pattern

Change your mowing direction each time. One week mow north-south, next week east-west. This prevents soil compaction and keeps grass blades standing upright instead of leaning one direction.

I know your neighbors in Ponte Vedra might judge you for the pattern in your lawn, but healthy grass beats pretty patterns every time.

Irrigation: Finding the Balance

This is tricky in March because rainfall can be inconsistent. Your lawn needs about 1 to 1.5 inches of water per week now that it's actively growing.

Set out tuna cans or rain gauges around your yard to measure how much you're actually getting from irrigation and rainfall combined. You might be surprised—most people overwater.

Best practices:

• Water early morning (4-8 AM)
• Water deeply but infrequently (2-3 times per week max)
• Adjust based on rainfall
• Make sure you're getting full coverage without overlap waste

In our sandy Jacksonville soil, water moves through fast. You want to encourage deep roots by watering deeply, not shallow roots by watering daily.

If you're in an area like Mandarin or Julington Creek with more clay mixed in, you might need to adjust. Clay holds water longer, so you might need less frequent watering.

Weed Management: The Battle Heats Up

If you put down pre-emergent in February, you're golden. If you didn't, you're about to see why you should have.

Post-Emergent for Existing Weeds

By March, you'll have plenty of weeds popping up:

Dollarweed (everywhere, especially in Ortega and Riverside where there's shade and moisture): Use a post-emergent with atrazine for St. Augustine, or a three-way broadleaf herbicide for other grass types.

Chamberbitter (common in Arlington and Westside): Tough one. Hand-pull young plants or use a selective herbicide. The key is catching it early before it sets seed.

Florida betony (mostly in older neighborhoods with established beds): This one's a pain. Selective herbicides work but might need multiple applications.

Sedges (yellow and purple nutsedge in low-lying areas): You need a specific sedge killer with sulfentrazone or halosulfuron. Regular broadleaf herbicides won't touch it.

Application Strategy

• Spot-treat rather than blanket-spray when possible
• Apply when weeds are actively growing
• Don't spray when temperatures are above 85°F (late March can get hot)
• Water in appropriately based on product label
• Be patient—some weeds need multiple treatments

Pest Watch: Chinch Bugs and Mole Crickets

March is when pests start becoming active again. Two big ones to watch for:

Chinch bugs: These tiny insects suck juice from grass blades, causing irregular yellow patches that eventually turn brown. St. Augustine is their favorite. Check for them in sunny areas, especially along driveways and sidewalks in places like Deerwood or Southpoint.

To check: part the grass at the edge of a damaged area and look for tiny black bugs with white wings. If you see them, you need an insecticide treatment.

Mole crickets: These tunnel through soil and eat grass roots. You'll see raised tunnels and irregular brown patches. They're more active at night. Do a soap flush test (2 tablespoons dish soap in 2 gallons of water, pour on suspected area) and they'll come to the surface if they're there.

Both pests are easier to control when populations are low. Don't wait until half your lawn is dead.

Disease Management: Still Vigilant

Brown patch can still be an issue in early March if we have cool, damp mornings. You'll see circular brown patches with that characteristic smoke ring.

Prevention:

• Water early morning only
• Improve air circulation
• Don't over-fertilize (creates lush, disease-prone growth)
• Remove thatch if it's excessive

If you get an outbreak, fungicides work, but fixing cultural practices prevents it from coming back.

Spring Renovation Work

March is prime time for renovation projects:

Dethatching

If you have more than half an inch of thatch (that spongy layer between grass and soil), it's time to dethatch. Too much thatch prevents water and nutrients from reaching roots and harbors pests and disease.

Rent a power rake or vertical mower. Go over the lawn once or twice, then rake up and haul away the debris. Your lawn will look rough for a week or two but will come back stronger.

Aerating

Core aeration relieves soil compaction and improves water infiltration. Even though we have sandy soil, high-traffic areas still get compacted.

This is especially helpful in areas like San Marco or Riverside where there's been years of foot traffic. Rent a core aerator, make two passes perpendicular to each other, and leave the plugs to break down naturally.

Overseeding (Limited Application)

You can't overseed St. Augustine—it doesn't grow from seed. But if you have Zoysia, Bahia, or Bermuda, you can overseed thin areas in March.

Prep the soil, spread seed at the recommended rate, keep it moist (not waterlogged), and you should see germination in 7-14 days depending on grass type.

Landscape Bed Maintenance

While you're working on the lawn, don't ignore the beds:

• Add fresh mulch (2-3 inches, not touching plant stems)
• Edge beds for clean lines
• Prune azaleas after they bloom (usually finishing up by mid-March)
• Fertilize shrubs and trees
• Plant warm-season annuals toward the end of the month

Good-looking beds make your lawn look even better. It's all connected.

Palm Tree Care

This is Jacksonville—we've got palms. March is a good time to fertilize them with a palm-specific fertilizer containing micronutrients like manganese and magnesium. Palms are heavy feeders.

Don't over-prune palms. Only remove completely brown fronds. Those green and yellow fronds are still providing nutrients to the tree.

Equipment Maintenance Continues

Keep your equipment in good shape:

• Clean your mower deck after each use
• Keep blades sharp (dull blades tear grass and invite disease)
• Change oil after every 25 hours of use
• Check belts and cables for wear

Running into friends at Ace Hardware on San Jose with broken equipment in April isn't fun. Stay ahead of it.

Water Restrictions and Conservation

Remember, Jacksonville has water restrictions (typically no watering between 10 AM and 4 PM). Check the current rules for your zone.

Even without restrictions, watering in the heat of the day wastes water through evaporation and can actually burn your grass if water droplets act as magnifying glasses.

Be a good neighbor and steward. The St. Johns River and our aquifer depend on smart water use.

Dealing with Shade

Got big oaks in Avondale or Riverside? Shade is tough on St. Augustine, even though it's the most shade-tolerant warm-season grass we have.

In deep shade:

• Raise mowing height to 4 inches
• Reduce fertilizer (shade grass needs less)
• Water less frequently (less sunlight = less transpiration)
• Prune tree branches to allow dappled light
• Consider shade-tolerant groundcovers in the deepest shade

Fighting nature is a losing battle. Work with what you've got.

Sod Installation

March is prime sod installation time. Soil is warm, rain is likely, and new sod has the whole growing season ahead to establish.

If you're putting in new sod in Nocatee or St. Johns County, make sure:

• Soil is properly prepared (tilled, graded, and amended)
• You install immediately after delivery
• You water daily for the first 2 weeks
• You stay off it for at least 3 weeks
• First mowing is light and only removes 1/3 of blade height

Don't cheap out on site prep. Good prep makes the difference between sod that lasts decades and sod that fails in two years.

March Action Checklist

Here's your game plan:

Week 1-2:

• First fertilizer application (when grass is actively growing)
• Begin weekly mowing schedule
• Adjust irrigation based on rainfall
• Scout for chinch bugs and mole crickets

Week 3-4:

• Continue mowing and irrigation management
• Post-emergent herbicide for visible weeds
• Aeration if needed
• Landscape bed maintenance

All month:

• Monitor for disease
• Keep equipment maintained
• Measure actual water application
• Remove weeds by hand when possible

Common March Mistakes

Don't do these:

• Fertilizing before grass is actively growing
• Mowing too short
• Overwatering
• Ignoring pest damage
• Applying herbicides in hot weather
• Leaving clippings in thick clumps

Looking Forward

Get March right and your lawn will cruise through April and May. You'll have established good mowing and watering routines, fertility will be dialed in, and weeds will be under control.

The lawns you admire in Ponte Vedra Beach, Sawgrass, and Beach Haven aren't accidents. They're the result of consistent care that ramps up properly in March.

This is the most important month of the year for setting up success. The work you put in now pays dividends all season. Take your time, do it right, and your lawn will reward you with thick, green growth that handles our brutal summer like a champ.

Get outside, enjoy the perfect March weather, and give your lawn what it needs. You've got this.