Turf experts often recommend “topdressing” lawns with a thin layer of compost. Depending on the weather and soil in the area, the material is spread out a quarter to half inch thick in the spring or fall. *.
Compost improves the moisture-holding capacity of the soil, adds nutrients, and feeds soil microbes. These microbes are key to the complex process that makes food available to grass plants. A healthy microbe population encourages a dense green lawn.
Compost spread on top of thatch can also speed thatch decomposition and eliminate the labor of mechanical removal.
Topdressing is the process of spreading a thin layer of compost or organic matter over your lawn. It helps improve soil health, fertilize grass, and level bumpy areas For topdressing, you want high-quality compost that’s weed and debris free Bagged composts offer convenience but can get pricey for large lawns. This guide covers the best bagged compost brands and what to look for when buying compost.
Why Topdress Your Lawn with Compost
Before getting into the best bagged composts, let’s look at why topdressing is beneficial:
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Feeds soil microbes – Compost contains beneficial bacteria, fungi, and other microbes that help break down thatch and recycle nutrients.
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Adds organic matter – Compost improves moisture retention and soil structure It also loosens compacted soil over time
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Provides nutrients – Compost contains nitrogen, phosphorus, potassium and micronutrients to fertilize grass.
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Reduces thatch – Microbes in compost help speed up decomposition of thick thatch layers.
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Smooths uneven areas – Spreading compost helps level low or bumpy spots in the lawn
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Increases drainage – Compost creates a more porous soil structure to improve drainage.
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Buffers pH – Finished compost has a neutral pH, so it can help balance acidic or alkaline lawn soils.
The key is spreading a thin, even layer at the right time of year for your climate. Most experts recommend 1/4 to 1/2 inch thickness. Now let’s look at the best bagged composts to use.
What to Look for in Bagged Compost
When shopping for bagged compost, check the label or description for:
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Mature compost – Fully finished compost without strong odors. Avoid soil, mulch, or unfinished mixes.
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Weed/debris free – Compost with no visible weeds, sticks, plastic, etc. Weed seeds or debris ruins the topdressing effect.
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Balanced nutrients – NPK ratio near 1-1-1 along with micronutrients. Avoid overly rich mixes that could burn grass.
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Safe ingredients – No biosolids, manure, or chemicals. Look for plant-based composts.
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Screened texture – Fine, sifted compost under 1/2 inch maximum particle size for even spreading.
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Low soluble salts – High salt content can damage grass roots. Under 4 mmhos/cm is ideal.
Getting all these qualities can be tricky in inexpensive bagged composts. Read on for brands that meet these standards.
The 6 Best Bagged Composts for Lawns
Here are my top picks for bagged composts suitable for topdressing lawns based on quality, consistency, and value:
1. Black Kow Composted Cow Manure
- Mature compost with no manure odors
- Balanced NPK ratio
- Weed seed and debris free
- Consistent quality batch to batch
Black Kow blends composted cow manure with peat moss and lime. It has an earthy fragrance, granular texture, and black color. The consistent quality and 1 cubic foot bags make this a winner.
2. Espoma Organic Lawn Food
- Made from plant materials, no manure
- Balanced nutrients with 5% iron
- Low odor and fine texture
- Can apply anytime except summer heat
Espoma Lawn Food is all-natural and sulfate-free. It contains compost plus pasteurized chicken manure for a gentle nitrogen boost. Suitable for any grass type.
3. Down To Earth Organic Lawn Topdress
- 100% plant-based ingredients
- Rich in beneficial microbes
- NPK for balanced feeding
- Low salt content
This OMRI-listed organic compost contains no biosolids or manure. A diverse mix of feedstocks ensures active biology and a range of nutrients.
4. Dr. Earth Lawn Topper
- Fast-acting natural fertilizer
- Probiotics and beneficial bacteria
- No manure or biosolids
- Also contains kelp meal
Dr. Earth Lawn Topper isn’t pure compost but a compost-based fertilizer. It provides a quick green-up along with organic nutrients to strengthen grass plants and roots.
5. Miracle-Gro Garden Soil for Flowers and Vegetables
- Affordable and available
- Screened, lightweight mix
- Feeds up to 3 months
- Use sparingly to avoid salt buildup
While not an ideal lawn compost due to higher salts, Miracle-Gro blends make decent budget-friendly options if used in moderation. Let rainfall leach salts.
6. Coast of Maine Bar Harbor Lobster Compost
- Composted lobster shells and sea products
- Also contains cow manure
- Rich in calcium, chitin, and microbes
- Use for coastal lawns with sandy soils
For a unique marine-sourced compost, Coast of Maine Bar Harbor is full of crab, lobster, and fish byproducts. Provides a slow-release boost of nutrients tailored for coastal acid soils.
Buying Bagged Compost in Bulk
Depending on your lawn size, buying compost by the pallet can save money. You may be able to special order quality brands like Black Kow or Espoma in bulk through nurseries, garden centers, or landscape material companies.
Another option is bulk-packaged compost from producers local to your area. Check with farms, municipal composting programs, land clearing companies, stables, or food waste recycling operations. Find options through the US Composting Council’s Find a Composter tool.
Should I Use Compost or Topsoil for Topdressing?
Look for compost, not topsoil. Quality topsoil can be used but may contain fewer nutrients and less organic matter than compost. Avoid “garden soil” blends that just mix compost and topsoil. Get 100% organic compost for the full benefits.
Be sure to scatter compost evenly using a drop spreader. Then water it in well to settle the compost and wash nutrients down into the soil. Your lawn will reap the rewards of improved soil health and fertility.
Complications of Topdressing
But there is a problem: Compost quality varies. So, how do you know if the compost you buy by the yard, pick up at the city’s leaf dump, or buy by the bag is “good”? Ask yourself these questions:
- Is it at the finished stage?
- Does it have things that you don’t want in it, like dyes or building materials?
- Are there viable weed seeds in the material?
- Could it have pesticide residues?
The parent materials and the composting process both affect the quality of the final product.
“There is only one way to know what compost contains,” says Al Rattie, director of market development at US Composting Council (USCC) in Bethesda, MD. “That is to use compost that has undergone compost-specific testing.”
Recognizing the problem this creates for consumers and the land care industry alike, the USCC started the Seal of Testing Assurance (STA) in 2000. STA is a testing, labeling, and disclosure program designed to bring visibility into the world of compost sales.
According to Rattie, STA is the only nationally recognized test.
STA looks at 14 compost characteristics including organic matter, salts, pH, major nutrients, pathogens, metals, stability, and maturity.
Rattie says one of the biggest concerns is the presence of pesticide residuals. Well-made compost, however, carries little of this risk.
“A proper composting system destroys the overwhelming majority of pesticides and herbicides,” says Rattie.
Unfortunately, consumers are not likely to find STA compost in big box stores. “Most STA members sell in bulk through direct sales, garden centers, and landscape supply yards in their area,” says Rattie.
USCC offers several resources to find STA compost and a calculator to help determine the amount:
- Find a list of 200+ STA participants
- Visit BuyCompost. com and use the compost calculator in the upper right corner of the home page.
Rattie strongly encourages anyone who is topdressing a lawn to use bulk compost.
“Bagged compost supplies only one cubic foot of material,” he says. “It takes 27 bags to get one cubic yard. Do the math!”.
When we used the compost calculator offered by the USCC at BuyCompost. com, we found that a one-quarter inch layer on a quarter-acre lawn (10,000 square feet) requires 7. 7 cubic yards or 5. 9 cubic meters of compost.
Rattie also encourages core aeration after the compost has been applied.
“Golf course and ball field superintendents having been using this technique successfully for many years,” he says.
Comparing Store Bought Bagged Soils to Find The Best One for Your Needs
FAQ
What kind of compost do you use for top dressing?
What is the best bagged soil for top dressing lawn?
Can I top dress with compost?
Should I Topdress my lawn with compost?
Turf experts often recommend “topdressing” lawns with a thin layer of compost. The material is spread one-quarter to one-half inch thick in spring or fall, depending on local climate and soil.* Compost improves the moisture-holding capacity of the soil, adds nutrients, and feeds soil microbes.
What size compost should I use for top-dressing?
Compost particles should be no more than 3/8” in size. The best compost for top-dressing is screened compost, as the particles are small enough to easily pass through the grass blades. Also, ensure that your compost doesn’t include plant seeds, as this may lead to a weed problem on your lawn down the line.
How many bags of compost do you need to topdress a lawn?
Visit BuyCompost.com and use the USCC’s compost calculator on the upper right of the homepage. Rattie strongly encourages anyone who is topdressing a lawn to use bulk compost. “Bagged compost supplies only one cubic foot of material,” he says. “It takes 27 bags to get one cubic yard. Do the math!”
Is compost good for your lawn?
Lastly, compost contains a healthy amount of carbon for your lawn’s soil. Carbon, although largely undervalued, plays a huge role in the overall health of your soil: Carbon feeds beneficial microbes, which affect soil structure, protects lawns from stress and breaks down nutrients in the soil,