How Fast Does St. Augustine Grass Spread?

As a longtime landscaper who specializes in St. Augustine grass, one question I’m asked constantly by homeowners is “How fast does St. Augustine grass spread?” While prized for its carpet-like texture and deep green hue, St. Augustine’s rapid lateral growth rate can take some homeowners by surprise.

In this comprehensive guide, I’ll leverage decades of hands-on experience to give you an in-depth look at everything that affects how quickly St. Augustine grass spreads. You’ll learn how climate, soil, variety, and care methods impact spread rate. I’ll also provide actionable tips to accelerate St. Augustine growth when establishing a new lawn, or slow it down if the grass is encroaching where it’s not wanted.

My goal is to equip you with the insider knowledge you need to manage the spread rate of St. Augustine grass. You’ll know what to expect in terms of growth pace based on your specific conditions. I’ll also answer the most common questions I receive about speed of spread after installation and St. Augustine’s potential to become invasive.

As an experienced landscaping pro, I hope to impart practical wisdom so you can get your St. Augustine lawn established and flourishing at just the right controlled rate for your unique needs. Let’s get growing!

What Factors Affect Spread Rate of St. Augustine Grass?

When homeowners ask me “how fast does St. Augustine grass spread?”, the first thing I explain is that growth rate isn’t constant. Many variables impact the speed and extent of lateral spread. Here are the key factors I’ve observed that affect St. Augustine grass growth rate over my years of landscaping experience.

Climate Conditions and St. Augustine Growth Rate

As a warm season grass, St. Augustine growth explodes in peak seasons and slows when temperatures drop. Here’s what I’ve noticed:

  • Hot and humid climates accelerate spread. Growth is fastest in Zone 9 and warmer.
  • Cool winters cause temporary dormancy. Lateral spread halts until temperatures rise again.
  • Coastal climates enjoy a longer active growing season. Inland areas experience more seasonal fluctuation.
  • Daily high temps above 80°F are optimal for rapid St. Augustine runner growth.

Understanding your local climate patterns allows you to predict growth rates based on seasonal shifts. St. Augustine grass thrives in subtropical conditions but adapts across a range of warm climates.

Soil Quality’s Impact on St. Augustine Lateral Growth

Fast Growing St. Augustine Grass

St. Augustine grass grows best in fertile, well-drained soil. Here are soil factors that affect spread rate:

  • Rich topsoil with ample organic matter enables the most rapid spread.
  • Nutrient deficiencies cause stunted, slow growth. Test soil and amend as needed.
  • Compacted clay soil restricts growth. Aerate regularly to enhance drainage.
  • Excessively sandy soil dries out faster. Irrigate more frequently.
  • Soil pH between 6.0-7.5 is ideal. Correct extremes with amendments.
  • New lawns need 2-4 inches of quality topsoil for optimal spread.

Analyze your soil and improve conditions before planting St. Augustine grass. Proper preparation pays off with faster establishment and coverage.

Now that you understand the key variables that impact lateral spread rate, let’s explore tactics to achieve your ideal St. Augustine grass growth pace.

Tips to Maximize Spread of St. Augustine Grass

Now that we’ve reviewed the major factors impacting lateral spread rate, let’s discuss pro tips to accelerate St. Augustine grass growth when establishing a new lawn. With some strategic care and maintenance, you can maximize spread to achieve full coverage faster.

Proper Watering Technique for Fast St. Augustine Growth

As a thirsty, fast-growing grass, St. Augustine needs ample irrigation to reach its rapid growth potential. Here are my watering best practices:

  • Water newly laid sod or plugs daily until established – about 2 weeks.
  • Irrigate early morning when evaporation is lowest. Avoid evening watering.
  • Topdress lawns routinely to improve moisture retention.
  • Adjust schedules seasonally, increasing frequency in hot, dry periods.
  • Aim for 1-1.5 inches of water weekly for active growth.
  • Consider installing in-ground sprinklers on a timer for convenience.
  • Monitor soil moisture routinely – don’t just rely on a schedule.

Proper irrigation technique keeps St. Augustine grass actively growing at peak rate through heat and dry periods. Deep, infrequent soakings are ideal.

Strategic Planting to Increase Pace of St. Augustine Spread

How and where you plant St. Augustine grass impacts how rapidly it spreads:

  • Use sod for instant coverage – it spreads from established edges.
  • Space plugs 6-12 inches apart for quicker fill-in.
  • Plant parallel to sidewalks, driveways and flower beds for efficient coverage.
  • Start from the farthest corner and work outward in sections.
  • Use borders and hardscape edges to your advantage.

Also, match the cultivar to your conditions for optimal growth:

  • Plant cold-tolerant varieties like ‘Raleigh’ in cooler climates.
  • Use heat/drought-tolerant ‘Amerishade’ in dry, desert regions.
  • Avoid dense shade varieties like ‘Palmetto’ in mostly sunny lawns.

Strategic planting and variety selection gives St. Augustine grass the best advantage for fast establishment and spread.

Now that you know how to maximize lateral growth, let’s look at signs of problematic spread and how to stop it.

When is St. Augustine Grass Spreading Too Fast?

While most homeowners want their St. Augustine lawn to fill in quickly, sometimes the grass spreads faster than desired. The “lawn invasion” creeps into flower beds, the driveway, or overwhelms neighboring grass.

In this section, we’ll cover signs of problematic spread along with tips to slow down rapid St. Augustine growth when it becomes invasive. With some diligent management, you can strike the right balance.

Signs of Excessively Rapid St. Augustine Growth

Based on my landscaping experience, here are red flags that St. Augustine grass is spreading too quickly:

  • Runners spread several feet or more annually
  • Creeping growth habit overwhelms flower and garden beds
  • Lawn encroaches far into hardscapes like driveways
  • St. Augustine chokes out and smothers other grass types
  • Rapid thinning and die back in extreme center of lawn

While a growth rate of 12+ feet per year is normal for St. Augustine, anything significantly beyond that signals overly aggressive spread.

Visually monitor your lawn’s boundaries and inspect for thinned out areas in the interior. Catch invasive spread early before it gets out of hand.

How to Slow Down Invasive St. Augustine Grass

If your St. Augustine grass is spreading too aggressively, here are my top tips to curtail growth:

  • Install physical borders and edges between lawn and garden beds.
  • Use landscape fabric around foundations and hardscapes to block spread.
  • Prune wandering runners regularly with a sharp blade.
  • Reduce nitrogen fertilization to discourage rapid growth.
  • Allow lawn to dry out slightly between waterings.
  • Mow frequently at lowest recommended height.

You can also replace invasive varieties like ‘Floratam’ with slower growing cultivars. ‘Delmar’ and ‘Classic’ are less aggressive options.

With some patience and persistence, you can wrangle rampant St. Augustine grass. My advice is to start control measures proactively before it colonizes unwanted areas.

Now that we’ve covered rapid spread issues, let’s go over the most frequently asked questions I receive on St. Augustine grass growth rate.

FAQ About Speed of St. Augustine Grass Growth

In my long tenure as a landscaper, I’ve fielded plenty of homeowner questions about how quickly St. Augustine grass spreads. Here I’ll cover some of the most common FAQs to help set realistic expectations.

How Long Does it Take St. Augustine Sod to Spread?

I’m often asked “how long before my St. Augustine sod fills in?” Here are the growth rates I typically see:

  • Established sod spreads up to 6-12 inches annually.
  • Full establishment takes 2-3 months with proper water and care.
  • Plugs planted 6″ apart fill in within 1-2 months.
  • 90% coverage can be expected within the first year.
  • Full maturity and maximum spread is reached after 2 years.

Be patient – resist the urge to plant plugs too far apart. Allow the sod or plugs to root thoroughly before accelerating growth.

What’s the Fastest Growing St. Augustine Grass Variety?

Growth rates can vary slightly among cultivars. Here are some of the fastest spreading varieties I recommend:

  • Raleigh – aggressive runner growth, up to 3′ per year.
  • Floratam – rapidly produces stolons up to 18″ annually.
  • Delmar – moderately quick-spreading, cold tolerant.
  • Palmetto – faster growing shade tolerance variety.

Avoid notoriously invasive varieties like Floratam unless you have plenty of space to fill.

Will St. Augustine Choke Out Other Grass?

Left unchecked, St. Augustine will overtake and choke out most other warm season grasses over time. Here are my tips:

  • Use edging and borders to contain St. Augustine and prevent encroachment.
  • If planting St. Augustine into existing lawns, keep plugs 12+ inches apart.
  • Mow frequently at lower heights to slow lateral growth.
  • Control growth rate with strategic watering and fertilization.
  • Monitor boundaries and prune wandering runners as needed.

With proper lawn preparation and vigilant management, St. Augustine can co-exist with certain grasses like zoysia. But plan ahead to prevent a monoculture from developing.

I hope this FAQ section has helped answer common questions about managing the rapid growth rate of St. Augustine grass. Let’s wrap things up with a quick recap.

Key Takeaways on St. Augustine Grass Spread Rate

After reading this guide as a seasoned landscaper, I hope you now feel equipped to manage the spread rate of St. Augustine grass for your unique needs.

We covered the key factors like climate, soil, variety, and care that impact the pace of growth. You learned strategic tips to accelerate lateral spread when establishing a new St. Augustine lawn, along with methods to curtail invasive growth. The FAQ section addressed common concerns like how long sod takes to fill in.

The key takeaways around maximizing an ideal St. Augustine spread rate are:

  • Match variety and planting methods to your conditions
  • Properly prepare soil and provide optimal care
  • Adjust water, fertilizer, mowing to control pace
  • Monitor growth habit and boundary encroachment
  • Start containment measures at first signs of invasive spread

With this knowledge of St. Augustine grass growth habits, you can better manage rapid lateral spread. I hope you feel confident in achieving your ideal coverage rate and have a thriving, beautiful St. Augustine lawn for years to come. Let me know if you have any other questions!

Scroll to Top