Fertilizing St. Augustine Grass: The Ultimate 2023 Guide

St. Augustine grass thrives with proper fertilization. This article provides the ultimate guide for fertilizing St. Augustine grass at the perfect time, with the right type of fertilizer, and in the correct amount for a healthy, lush lawn.

Why Fertilize St. Augustine Grass?

Fertilizing St. Augustine grass is essential for maintaining its vibrant green color, preventing nutrient deficiencies, and promoting healthy growth. Here are some key benefits of fertilizing:

• Enhances root development and overall plant health
• Improves drought tolerance and heat resistance
• Promotes thick, lush growth and a dense lawn
• Prevents yellowing, browning, and nutrient deficiencies

When to Fertilize St. Augustine Grass

The optimal time to fertilize St. Augustine grass is during its active growing season, which typically occurs from March to November in most regions. Fertilizing in the spring promotes healthy growth, while fertilizing in the fall helps prepare the grass for winter.

Spring Fertilization: Apply a balanced fertilizer with a nitrogen-phosphorus-potassium (NPK) ratio of 16-4-8 or 15-5-10 in March or April.

Fall Fertilization: Use a slow-release fertilizer with a higher potassium content (e.g., 12-4-8 or 10-4-10) in September or October.

Choosing the Right Fertilizer

When choosing a fertilizer for St. Augustine grass, look for products that are specifically formulated for warm-season grasses and contain the following nutrients:

• Nitrogen (N): Essential for leaf growth and green color
• Phosphorus (P): Promotes root development and overall plant health
• Potassium (K): Helps with water absorption, disease resistance, and winter hardiness
• Iron (Fe): Prevents yellowing in alkaline soils

How Much Fertilizer to Apply

The amount of fertilizer to apply depends on the size of your lawn and the soil conditions. As a general rule, apply 1 pound of nitrogen per 1,000 square feet of lawn every 4-6 weeks during the growing season.

Approximate Fertilizer Application Rates:

How to Fertilize St. Augustine Grass

Applying fertilizer evenly is crucial for optimal results. Here are some tips for effective fertilization:

1. Calibrate Your Spreader: Ensure your fertilizer spreader is calibrated to the correct rate for the product you are using.
2. Apply in Multiple Passes: Spread the fertilizer in two or three overlapping passes to avoid clumping and uneven distribution.
3. Water Thoroughly: Water your lawn deeply after fertilizing to activate the nutrients and prevent fertilizer burn.

Additional Tips for Fertilizing St. Augustine Grass

• Avoid Overfertilizing: Applying too much fertilizer can damage your lawn. Follow the recommended application rates and avoid overfeeding.
• Use a Balanced Fertilizer: Choose fertilizers that contain all three essential nutrients (nitrogen, phosphorus, and potassium) in a balanced ratio.
• Fertilize Regularly: Fertilize your St. Augustine grass every 4-6 weeks during the growing season to maintain healthy growth.
• Test Your Soil: Conduct a soil test every few years to determine the nutrient needs of your lawn and adjust your fertilization program accordingly.

Troubleshooting Fertilizer Issues

Nutrient Deficiencies: Yellowing leaves, stunted growth, and weak root systems can indicate nutrient deficiencies. Identify the deficient nutrient and apply a fertilizer that contains the missing element.

Fertilizer Burn: Applying too much fertilizer or applying it during hot weather can cause fertilizer burn. Signs include brown or scorched patches on the lawn. Water your lawn deeply and avoid fertilizing during extremely hot weather.

FAQs about Fertilizing St. Augustine Grass

Q: When is the best time to fertilize St. Augustine grass?
A: Fertilize in the spring (March-April) and fall (September-October).

Q: What is the best fertilizer for St. Augustine grass?
A: Choose a balanced fertilizer with a 16-4-8 or 15-5-10 NPK ratio and slow-release nitrogen.

Q: How much fertilizer should I apply to my St. Augustine lawn?
A: Apply 1 pound of nitrogen per 1,000 square feet of lawn every 4-6 weeks.

Q: Can I overfertilize my St. Augustine lawn?
A: Yes, applying too much fertilizer can damage the lawn. Follow the recommended application rates and avoid overfeeding.

Q: What should I do if my St. Augustine lawn is showing signs of nutrient deficiency?
A: Identify the deficient nutrient and apply a fertilizer that contains the missing element.

Q: Can I fertilize my St. Augustine lawn during the summer?
A: Yes, but apply fertilizer sparingly and water deeply after application. Avoid fertilizing during extremely hot weather.

Q: How often should I water my St. Augustine lawn after fertilizing?
A: Water deeply after fertilizing to activate the nutrients and prevent fertilizer burn.

Q: Can I use a weed-and-feed product on my St. Augustine lawn?
A: Yes, but be sure to choose a product that is specifically formulated for warm-season grasses.