Pythium Disease on Lawns: The Role of Weather and the 150 Rule

2024 has been a challenging year for lawn care, especially in regions like the Northeast where cool season grasses are abundant (cool season grasses are more susceptible to Pythium). If your lawn has been struggling despite your best efforts, you are not alone. This year’s weather conditions have been a perfect storm for Pythium disease, causing it to be an issue across many lawns in Connecticut.

The 150 Rule of Pythium Disease

Most simply put - Pythium is a fungus that is a soil-borne organism.  It’s out there lurking in so many of our lawns, just waiting for the perfect moment for it’s spores to flare up and spread when this pathogen is present. 

Two main factors that contribute to a Pythium disease flare up are heat and humidity.  This is where the “150 Rule" comes into play.  

According to the 150 rule - pythium is very likely to flare up (when the pathogen is already present) when, for three consecutive days, the combined daytime temperature plus humidity levels exceed 150. 

Another easy way to follow this rule is to combine daytime and nighttime temperatures.  When this exceeds 150 degrees, we are in prime pythium blight disease territory.

Here are some examples of the 150 rule with pythium disease:

• Daytime high of 90 degrees F plus nighttime low of 60 degrees F

• Daytime high of 80 degrees F plus humidity levels of 70%

• 65% humidity plus daytime highs of 85 degrees F

In Hartford, CT in 2024, around 60 of 75 days between June 1st and August 15 have met this criteria. 

This means that for the majority of the summer, we have had perfect conditions for this aggressive lawn disease to thrive and spread. Between June - August in Connecticut we can typically see an average humidity level of 70%.  We have had excessive heat in 2024 which has made this year especially tough for lawn diseases. 

Why Are We Seeing So Much Pythium This Year?

The 2024 summer has been unusually hot and humid, which are the exact conditions that Pythium thrives in. When these conditions persist, the spore counts can explode. 

This year’s weather patterns have created what is known as the "Disease Triangle," where the combination of a susceptible host (your grass), a pathogen (Pythium fungi present in the soil), and the environment (hot, humid weather) has triggered an increase in lawn diseases.

Why Young Lawns Are More Susceptible to Pythium

Young lawns, in particular, are more susceptible to weeds, diseases, insect damage…and pythium is no exception to this.  This is because they lack the established root systems and resilience that older, more mature lawns have. 

What Can You Do About Pythium?

If you’re noticing signs of lawn stress, it’s crucial to determine whether it’s drought stress or Pythium. Many people think their lawn is suffering from drought and try to compensate by watering more. However, if the issue is Pythium, additional watering can make this problem worse.

In going back to the Disease Triangle - we need 3 things for a lawn disease to be present.  Of these 3 criteria, we need to control what we can control. 

1. Host (grass): We can control this by planting A-list certified grasses that are tested to see which best withstand pressures like drought and disease. 

2. Pathogen (soil-borne pythium)

3. Environment (hot/humid)

• Stop Watering Your Lawn: If you suspect Pythium, halt watering immediately. Pythium thrives in wet conditions, so continued watering can accelerate its spread.

• Ensure proper drainage. Avoid water logged root zones. Manage thatch, manage compacted soil and manage shade to make sure you have no pooling areas in your lawn. 

Call Your Lawn Care Company: Reach out to a professional lawn care company to diagnose the problem. They can determine whether it’s Pythium or another issue and apply the appropriate fungicide to stop the spread.

The summer of 2024 has created the perfect conditions for Pythium to flourish, particularly in areas like Hartford, CT. By understanding the 150 Rule and the environmental factors that contribute to this disease, you can take proactive steps to protect your lawn. Remember, early detection and proper management are key to minimizing the impact of Pythium on your lawn. If you’re unsure about what to do, don’t hesitate to contact a lawn care professional for expert advice.

Soil Types in Connecticut - How Soil Affects Your Lawn Care Program

When we think about the factors that go into having a beautiful lawn, we often think about lawn fertilization, grass seed type, lawn aeration or an irrigation system.  One factor that often gets overlooked is soil type. 

The type of soil in your lawn directly impacts how well your lawn can hold moisture which is imperative for growing healthy plants. 

What kind of soil do we have in CT?

What we see a lot of in Connecticut is a sandy loam soil.  Sandy loam soil is considered soil that has 20% or less of clay and 52% or more of sand. 

While sandy loam soil is the majority, Connecticut does offer some diverse topography and climate, resulting in a wide range of soil types. These diverse soil types play a significant role in shaping the success of lawn care practices throughout the state.

What are some of the different types of soil found in Connecticut?

1. Sandy Soil: Sandy soil is found in coastal regions and areas with glacial deposits. It has a gritty texture, good drainage properties, and low fertility. While its fast-draining nature makes it less prone to waterlogging, sandy soil tends to dry out quickly, requiring more frequent irrigation. Sandy soil can heat up quickly due to its high air content, leading to higher risk of drought and heat stress to your lawn.  Fertilizer and organic matter amendments are often necessary to enhance nutrient retention and improve soil structure.

2. Clay Soil: Clay soil is commonly found in Connecticut's inland areas. It is composed of fine particles that compact easily, resulting in poor drainage and a tendency to retain water. Clay soils can become waterlogged and sticky when wet, making it difficult for grass roots to penetrate and get necessary oxygen. What to do if you have a clay lawn? Include lawn aeration, regular top-dressing with organic matter, and the addition of gypsum to improve drainage and enhance soil structure to your yearly lawn maintenance schedule. 

3. Loam Soil: This is considered the most ideal soil type for grass growing.  Loam soil is a balanced mixture of sand, silt, and clay. It offers good drainage while retaining moisture and nutrients.  Loam soil is commonly found in Connecticut’s valleys and river basins. Regular fertilization, proper watering techniques, and routine aeration can help maintain the health and vigor of lawns grown in loam soil.

4. Silty Soil: Silty soil is often found near rivers and floodplains.  It is composed of fine particles that offer excellent moisture retention. It is typically fertile but can be prone to compaction when wet. Silty soil benefits from organic matter additions and periodic aeration to improve its structure and prevent waterlogging. Additionally, maintaining proper drainage is crucial to prevent root rot and other moisture-related issues.

Not all lawns are equal

Understanding the characteristics and challenges posed by different soil types in Connecticut is essential for effective lawn care. Conducting a soil test to assess pH levels, nutrient deficiencies, and organic matter content is a great starting point. Once you have this information, it’s easier to make sure you are tailoring your practices to just what your lawn needs.

What Are The Fillers in a Bag of Fertilizer?

Understanding Fertilizer Fillers

Fertilizers play a crucial role in a lawn care program.  Fertilizers deliver essential nutrients to lawns.  

We often get asked a slew of questions from customers such as:  “Why didn’t my fertilizer absorb into my lawn?” “What are those pebbles left behind” “Is the fertilizer working if I still see it on the ground?”

While we completely understand the concern, you need not worry!  Often what you are seeing left behind is fertilizer fillers or carriers. 

What Are Fertilizer Fillers?

Fertilizer fillers are inactive ingredients that allow us to control and dilute the concentration of nutrients and products, they ensure that there is no clumping, they aid in even distribution, and they facilitate easier application.  

Purpose and Benefits of Fertilizer Fillers:

1. Physical properties: Fillers can enhance the physical properties of fertilizers, making them more free-flowing, granulated, or pelletized. By improving the handling, fillers prevent caking or clumping, making it easier to apply.

2. Nutrient Control: Certain fillers act as slow-release agents, helping to control the release of nutrients over time. This gradual release ensures that plants receive a steady supply of nutrients, reducing the risk of nutrient loss through leaching and minimizing the potential for fertilizer burn.

Types of Fertilizer Fillers:

1. Inert Materials: Materials such as sand, clay, diatomaceous earth, and perlite are commonly used as fillers due to their low cost and availability. These inert substances do not contribute any significant nutrients but help to improve the physical properties of the fertilizer.

2. Organic Fillers: Organic materials like peat moss, sawdust, and compost can serve as fillers. These materials may add some organic matter to the soil, promoting improved soil structure, water retention, and microbial activity. However, the nutrient content in organic fillers can vary, and they should be carefully selected to avoid introducing weed seeds or pathogens.

3. Sulfur and Lime: Sulfur and lime are occasionally used as fillers in specific fertilizers. Sulfur can help acidify alkaline soils, while lime can raise the pH of acidic soils. These fillers provide additional benefits alongside the nutrient content of the fertilizer.

Since 2007, Green Meadow Lawn Care has provided homeowners throughout the greater Tolland, Connecticut area with premium fertilization programs, tick control, mosquito management, seeding & aeration and tree & shrub care. 

Visit our Learning Center to find out more about how our services can help you or visit our Youtube Channel to view more in our Learning Center Series.

To speak to our Customer Service Manager, please call Dave (view Dave's video bio here) with any questions. Dave has been in the industry for 30 years and is always happy to help with his expert advice.  

860-870-5700

Acidic Soil in the Northeast

Acidic soil is a common issue in the Northeast US. The Northeast is characterized by a humid and rainy climate with dense forests which leads to soil that is naturally acidic. 

Naturally acidic soil can cause problems for plants and crops that require neutral or alkaline soil.  Grass, in particular, prefers a soil pH of 6.5-7 which happens to be very slightly acidic. 

Causes of acidic soil in the Northeast:

What’s the main cause of the slightly acidic soil in the Northeast?  The amount of annual rainfall is the leading factor. Rainfall tends to leach away the alkaline elements in soil like calcium, magnesium and potassium.  Sandy soil is often the first type of soil to leach because water can move through it easily. 

Other causes of acidic soil:

• Overwatering lawn: overwatering your lawn can speed the process of  important micronutrients leaching away. 

• Fertilizers with too much nitrogen: be careful to always read your labels and choose the right products for your location and climate. 

• Removing grass clippings.  This can carry away significant amounts of calcium and magnesium that would otherwise be recycled.

Signs of acidic soil:

• Yellowing leaves

• Poor growth

• High volume of moss and lichen growth which grow well in acidic soil

• High volume of oak and pine trees which also thrive in acidic soil 

• Fungal diseases

• Low pH levels 

If you notice any of these signs, it may be a good idea to test the pH of your soil and take steps to correct the acidity if necessary.

How does lime help my lawn?

Adding lime into a lawn program is a common practice in Connecticut and the Northeast.  Remember - Limestone is not a fertilizer, it’s a soil amendment.  It is made from ground-up limestone rock and deposits calcium carbonate and magnesium carbonate back into soil. 

In addition to enhancing soil quality and nutrient availability, Lime can also boost the effectiveness of fertilization programs and promote better water absorption in lawns. 

By conditioning the soil and raising calcium levels, Lime plays a crucial role in promoting cell wall division, which is vital for overall plant growth and development.

Grass Seed Germination Tips

Tips to maximize Grass Seed germination:

Grass seed germination is the process by which grass seeds sprout and grow into new grass plants. 

Seeding a lawn can be a big investment.  A big part of your lawn’s success is actually what happens after the seeding job is complete.

Why does grass seed germination matter in lawn care?

Grass seed germination determines when your lawn care treatment begins and ends each year. 

Soil temperature vs Air temperature

Grass seed germination is tied very closely to soil temperature. Soil temperature is NOT the same as air temperature.  If the air temps are 65 degrees, it does not mean the ground temperature is also 65 degrees.  Soil acts as an insulator.  The pores in soil will keep temperatures hot when they reach a warm point and cool when they reach freezing temperatures.  

Factors to consider for success:

• Quality of grass seed

• Quality of soil - sandy lawns 

What triggers grass seed to germinate?

Temperature! And no, not air temperature but ground temperature.   Whether you plant your grass in the fall, winter or Spring, grass seed will not germinate until soil temperatures are above 50 degrees.  

When is the best time of year to plant grass seed?

We have seen the most success with fall seeding.  Fall seedings allow grass 2 full seasons to grow and establish plants. They will be nice and hearty and ready to fight the pressures of heat and disease that come with summer time. 

How long does is take grass seed to germinate?

There are many contributing factors but you can generally expect grass seedlings to emerge anywhere between 7 and 21 days.  Avoid mowing your lawn for a minimum of 3 weeks to allow new grass to establish.  

Tips for maximizing grass seed germination:

1. Choose the right grass seed: Different types of grass seeds have different germination rates and requirements. Consult with a local nursery or landscaping professional to determine the best type of grass seed for your climate and soil type. Here in the northeast we have cool season grasses.  If you live in the south, you might have more success with warm season grasses like Zoysia, Bermuda or Centipede grass. 

2. Prepare the soil: Before planting grass seed, make sure the soil is prepared properly. Remove any weeds, debris, or rocks from the planting area. Loosen the soil with a shovel or tiller to allow the roots of the grass seedlings to grow easily.  Professional lawn care companies will use an Aeration vehicle that can loosen soil with a few passes over your lawn. 

3. Plant at the right time: The best time to plant grass seed depends on your climate and the type of grass seed you are using. In general, cool-season grass seeds (such as Kentucky bluegrass and perennial ryegrass) are best planted in the fall, while warm-season grass seeds (such as bermudagrass and zoysiagrass) are best planted in the spring or early summer.

4. Use the right amount of seed: Follow the recommended seeding rate for the type of grass seed you are using. Planting too much seed can lead to thin, weak grass, while planting too little may result in patchy, bare areas.

5. Water regularly: Grass seed needs consistent moisture to germinate and grow. We recommend that your first watering be HEAVY to set the seed then daily for 3 weeks to keep the seed bed moist (but not waterlogged). Once the seedlings have sprouted and the grass has become established, you can reduce watering to once or twice a week.

6. Protect the seedlings: Keep the seedlings protected from heavy foot traffic, leaves and mowing.  Avoid mowing for 3 weeks or until grass is about 5 inches high.  When you resume mowing, the height should be between 3.5-4 inches high. 

7. Nourish seedlings: Use a grass seed starter fertilizer to give the seedlings the nutrients they need to grow strong and healthy.

By following these tips, you can help ensure that your grass seed germinates and grows into a healthy, lush lawn.