Knowing when to fertilize Bermuda grass is the single most important factor for achieving a thick, green, and resilient lawn. If you get the timing right, everything else becomes easier. This guide will walk you through the optimal timing for growth, season by season, so you can build a lawn that’s the envy of the neighborhood.
A well-fed Bermuda lawn is a powerhouse, spreading quickly, resisting weeds, and recovering from stress. But fertilizing at the wrong time can waste your money, harm the grass, and even help weeds take over. Let’s break down the perfect schedule.
When to Fertilize Bermuda Grass
The core principle for Bermuda grass is to fertilize during its active growing season, which is when soil temperatures are consistently warm. Bermuda is a warm-season grass, so it greens up in late spring, grows vigorously all summer, and goes dormant (turns brown) after the first hard frost in fall.
Understanding the Growth Cycle of Bermuda Grass
To fertilize correctly, you need to think like the grass. Its growth is directly tied to soil temperature.
– Spring Green-Up (Soil temps ~55°F): The grass begins to wake from dormancy. It’s using stored energy, so don’t fertilize too early.
– Peak Growth (Soil temps 65°F – 90°F): This is the prime feeding window. The grass is actively growing roots and shoots.
– Fall Slowdown (Soil temps below 65°F): Growth slows as the grass prepares for winter. Fertilization must stop.
– Winter Dormancy (Soil temps below 50°F): The grass is brown and not growing. No fertilizer is needed or advised.
The Seasonal Fertilization Schedule
Follow this simple, four-step seasonal plan for best results.
1. Late Spring: The First Application
This is your starter application. Wait until the lawn is fully green and has been mowed at least twice. This usually happens when soil temperatures are consistently above 65°F, often in late April or May.
– Why then? Early fertilization forces tender new growth that can be damaged by a late frost. It also feeds winter weeds like poa annua.
– What to use: Apply a balanced, slow-release nitrogen fertilizer. A ratio like 16-4-8 or 15-5-10 is a great choice. The slow-release formula feeds the grass steadily over 6-8 weeks.
2. Summer: The Main Feeding Period
From early summer through late summer, Bermuda is in its glory. You can plan for 2-3 applications during this period, spaced 4-6 weeks apart.
– Early Summer (June): Apply your second dose of fertilizer. This fuels the rapid lateral growth that thickens the lawn.
– Mid-Summer (July): A third application maintains color and vigor during the heat. Ensure deep watering to prevent burn.
– Late Summer (August): This is often the final nitrogen application. Do not apply high-nitrogen fertilizer too late in the season.
A key summer tip is to watch the weather. Don’t fertilize right before heavy rain (it can runoff) or during extreme drought (it can burn the roots).
3. Early Fall: The Important “Winterizer”
This is a critical and often misunderstood step. About 4-6 weeks before your expected first frost, apply a fall or winterizer fertilizer.
– Timing is everything: For most, this is September or very early October.
– What’s different? Use a fertilizer low in nitrogen but high in potassium (the third number, like 5-10-30). Potassium strengthens cell walls, improves drought tolerance, and enhances cold hardiness, helping the grass survive winter.
– Do not apply high nitrogen in fall. It stimulates soft, new growth that will be killed by frost, weakening the entire plant.
4. Winter: No Fertilization
When Bermuda is dormant and brown, it is not growing. Applying fertilizer now is useless and can pollute waterways. Let it rest.
How to Choose the Right Fertilizer
Reading the bag is simple once you know the code. All fertilizers display an N-P-K ratio (Nitrogen-Phosphorus-Potassium).
– Nitrogen (N): For green, leafy growth. This is the most important nutrient for Bermuda.
– Phosphorus (P): For root and seedling development. Most established lawns have enough phosphorus; a soil test can tell you for sure.
– Potassium (K): For overall plant health, stress tolerance, and disease resistance.
For most summer applications, a fertilizer with a 3-1-2 ratio (like 21-7-14 or 15-5-10) is perfect. Always opt for slow-release nitrogen when possible—it feeds consistently and reduces the risk of burning.
Step-by-Step: How to Apply Fertilizer Correctly
Doing it right ensures the grass gets the food and you don’t harm the environment.
1. Mow the lawn a day or two before you apply fertilizer.
2. Water the lawn lightly the day before if the soil is very dry.
3. Calibrate your spreader. This step is often skipped, but it’s crucial for even application. Follow the settings on the fertilizer bag.
4. Fill the spreader on a hard surface, like a driveway, to avoid spills on the grass.
5. Apply using a pattern: Walk at a steady pace. Start around the perimeter, then go back and forth in parallel lines, slightly overlapping each pass to avoid streaks.
6. Water it in thoroughly after application, unless the bag directs otherwise. This washes the granules off the grass blades and into the soil.
Essential Pre-Fertilization Step: The Soil Test
A soil test is like a blood test for your lawn. It tells you exactly what nutrients are lacking or are in excess. You can get a kit from your local county extension office. It will give you precise recommendations for lime, phosphorus, and potassium, taking the guesswork out of fertilization. It’s the best $15 you can spend on your lawn.
Common Fertilization Mistakes to Avoid
Even experienced gardeners can make these errors. Here’s what to watch out for:
– Fertilizing too early in spring. Patience is key.
– Using the wrong fertilizer ratio. Don’t just grab any bag.
– Applying fertilizer to wet grass. Granules will stick and burn the blades.
– Not watering it in properly. This can lead to volatilization or burn.
– Over-fertilizing. More is not better! It leads to thatch buildup, excessive mowing, and pollution.
– Ignoring local ordinances. Some areas restrict phosphorus or have fertilizer blackout periods in summer.
FAQ: Your Bermuda Grass Fertilization Questions Answered
Q: Can I fertilize Bermuda grass in October?
A: It depends on your climate. Only apply a fall/winterizer fertilizer (high potassium, low nitrogen) if it’s at least 4 weeks before your average first frost. For southern areas, this may be fine; for northern zones, it’s likely too late.
Q: How often should you fertilize Bermuda grass in summer?
A: Generally, every 4 to 6 weeks during active growth, depending on the type of fertilizer used. Slow-release formulas allow for longer intervals.
Q: What is the best fertilizer schedule for Bermuda?
A: A classic schedule is: 1) Late spring (balanced), 2) Early summer (nitrogen), 3) Mid-summer (nitrogen), 4) Early fall (potassium-heavy winterizer).
Q: Is it too late to fertilize Bermuda in September?
A: Not necessarily. September is often the ideal time for the final fall potassium application in many regions. Avoid any high-nitrogen feeds.
Q: Should you fertilize before or after rain?
A: Definitely before, but with caution. Apply fertilizer when no heavy rain is forecasted for 24-48 hours to prevent runoff. A light rain after application is perfect, otherwise, water it in yourself.
Q: Can you over fertilize Bermuda grass?
A: Absolutely. Signs include yellowing or browning (burn), excessive thatch, rapid growth requiring constant mowing, and increased susceptibility to disease. It also stresses the grass plants.
By following this timing guide, you work with your Bermuda grass’s natural cycle, not against it. The result is a lawn that is not only beautiful but also stronger and more self-sufficient. Consistent, timely feeding is the secret to a turf that can handle play, heat, and time. Start with a soil test, mark your calendar for late spring, and enjoy the process of nurturing your green space.