Why Does My Yard Smell Like Fish? The Top 3 Reasons

Are you tired of your lawn looking and smelling gross? The neighbors probably can’t stand it either. You’re not alone, though; Countless homeowners have dealt with awful odors drifting from the grass, but how can they deal with the common problem?

Your yard smells like fish because of fungal growth, Bradford pear trees, or rotting compost bins. Pythium fungus is the main culprit. It leads to root rot and stickiness that spreads throughout the lawn. Use fungicides for the fungus, and don’t forget to aerate your compost pile.

Throughout this post, you’ll learn the following details about why your yard smells like fish:

• Three of the main reasons that can make lawns smell foul
• Several treatment suggestions to bring your lawn back to life
• Preventative measures for long-term grass growth

My Suggestion: Fungus is the leading cause of fishy odors in gardens and lawns. You can combat them with all sorts of solutions, but don’t forget to clean your mower’s blades to prevent it from spreading. Try looking through the best fungicides for lawns on Amazon. They take a couple of weeks to work, but it’s better than a few months of foul odors!

Here’s Why Your Yard Smells Fishy

According to The Post and Courier, odd odors on grass often come from fungus. There are plenty of other causes, so let’s dive into all of them below.

Pythium fungus

Pythium fungus is a fungus known to cause brown rot of grass-root tips, the stems, and the cortex that progresses up the stem. It’s usually present on all grass types, and it requires the right conditions for it to thrive.

Root rot often occurs during warm nights (68 degrees F) and warm days (86 degrees F) that are accompanied by rainy weather. Low spots in the lawn that retain water and the shaded parts that retain moisture attract fungi. It flourishes in high temperatures and water-logged soil since it’s waterborne.

During the seeding period, additional water on the lawn provides the conditions necessary for the fungi to flourish. Lush growth due to nitrogen application on the lawn is also likely to be attacked by fungi.

Grass that’s infected by fungi leads to stunted growth, circular patches during warm and humid conditions, yellowing of the lower leaves, and in extreme cases, the death of the plant.

The circular spots in the grass appear water-soaked and dark early in the morning. This problem occurs if your yard has poor drainage that results in insufficient oxygen supply. The grass’s fishy odor is due to a combination of poor drainage, rotting grass stems, and decaying root tips.

Pythium root rot makes the grass feel sticky when you rub it between your fingers. The fungi are effectively suppressed through treatments, and frequent fungicide drenches.

The Presence of Bradford pears in your yard

Southern Living shows us that Bradford pear trees can wreak havoc on a lawn. The Bradford pear is a tree with a fairly white appearance. Its weak branching structure and thick limbs that overshadow your lawn hinder the growth of grass underneath.

The Bradford pear flowers that appear during the springtime give off a fishy odor that’s very unpleasant. The presence of Bradford pears in your lawn or within your vicinity could be the source of the fishy smell. A lawn area that’s shaded by the tree is prone to fungi infection because of the excess moisture retention that contributes to the fishy smell.

You can plant alternative types of trees instead of the Bradford pear, such as the Crapemyrtles. They include American hornbeam, Serviceberry, fringe tree, Pagoda dogwood, yellowwood, flowering dogwood, American smoke tree, green hawthorn, Eastern hophornbeam, and Carolina buckthorn.

Compost bins can cause fishy-smelling grass

A healthy compost pit has a balance of both brown materials like dry leaves and green materials such as fresh lawn clippings and food craps. You should turn the compost frequently to allow enough oxygen to penetrate for decomposition to take place.

Too much water in a compost bin causes the compost to stink. This creates an unpleasant environment in your yard. In case your compost is too wet, dig it out entirely and turn the pile to allow air circulation before restacking it. Proceed to add the dry materials to improve its drainage.

How to Make Your Yard Not Smell Like Fish

There are a number of treatments that you can use to get rid of the fish smell in your yard. They include:

Use Fungicides

For fungicides to work effectively, you must apply it before the grass dies. There are two types of fungicides that are available for home use; contact fungicides and systemic fungicides. Contact fungicides are applied at the early stages of the fungal infection to prevent its spread, while the systemic fungicides work from the inside of the grass plant to prevent problematic fungus. For better satisfying results, it’s advisable to seek professional assistance. The following fungicides can be used:

• Plant health fungus control should be used. This product can be used as a spot treatment on lawns. Spray it on the lawn and also on the soil. It’s drawn into the grass plant to prevent it from further spreading the fungal growth.
• Signature stressgard is another recommendation. This is a systemic fungicide that controls turf diseases such as Pythium. It enhances your turf health and minimizes the stress that’s resulting from both the biotic and abiotic sources.
• Banol fungicide is advisable as well. This is also a systemic fungicide that’s reliable for controlling Pythium fungi. It’s advisable to apply it early for the best results to prevent later outbreaks and turf injury.

Plant scented plants in your yard

Adding scented plants in your yard improves its fragrance and adds an extra layer of richness and beauty to your landscape. These scented plants can be planted in pots and containers then placed by the front door, along the walkways, or near the windows where the breeze will spread its scent.

Examples of scented plants include Hyacinth, Magnolia, Gardenia, Wisteria, Sweet Alyssum, Honeysuckle, Roses, Phlox, Butterfly Bush, Flowering Crabapple, Peony, Dianthus, Stock, and Korean spice Viburnum.

How To Prevent It from Happening

The following tips can be applied to prevent or avoid fungal infection or reinfection of the lawn:

1. Collect and toss grass clippings

Grass clippings from the affected section of the lawn may retain the fungus spores in the lawn. After mowing the lawn, collect all the grass clippings and toss them. 

Want to use clean, healthy grass clippings for mulch and grass growth?

 2. Keep your grass adequately fertilized and watered

Proper and effective fertilizing and efficiently watering your lawn ensures that you have healthy grass that can fight off a fungal attack. Check out my review of the popular Scotts Natural Lawn Food (recently replaced by a new system from the same company, which is covered in the article).

3. Ensure your mower blades are sharp and clean

Sharpen your mower blades when you notice that they have become blunt. Never forget to clean them regularly, especially when you’re dealing with odd scents, textures, and appearances. This is because wounded, clogged grass blades attract fungal infection.

4. Keep your grass 2 to 2 ½ inches long

Cutting your lawn either too short or letting it grow dense interferes with air circulation in the lawn. This ultimately attracts fungal spores. A thick thatch longer than ½ an inch isn’t advisable. De-thatch using a vertical mower and then rake up the debris.

5. Fill the holes in the lawn

Depressions or low spots in the lawn retain moisture and create perfect conditions for fungal spores to spread. The shaded areas that retain dew and rainwater longer than other sections in the yard also contribute to its spread. Fill up these depressions to curtail the fungi growth.

Wrapping It Up

You don’t have to deal with a lawn that smells like fish. We all know that grass has a uniquely fresh scent, so why deal with gross odors? Fortunately, you now know everything about why your lawn needs to have a cleansing project for the next few weeks.

Here’s a quick recap:

• Fungus is the number one cause of fishy grass and stickiness.
• Bradford pears are a common problem that leads to unpleasant odors.
• Use fungicides, mow regularly, and clean your blades after every trim.

Is your grass sticky? Click here.