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Does Mulch Go Bad? (Tips for Prolonging Mulch Shelf-Life)

Does Mulch Go Bad? (Tips for Prolonging Mulch Shelf-Life)

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Mulch is a dry material that you can store for years. You can keep it indefinitely if you leave it in ideal conditions.

However, mulch can go bad, and it’s hard to tell once it is. Being aware of the signs may save your plants from getting ruined!

Today, we’ll discuss the signs of bad mulch and teach you how to prolong its shelf-life.

Let’s dive in!

How Long Does Mulch Last?

By itself, mulch can last 4-7 years. It’ll still have the same ability to suppress weeds and retain soil moisture even years after harvest.

Moreover, you can prolong its shelf life if you store it properly!

If your mulch is in a bag, you can poke holes into the plastic to allow air to flow. You should keep it in an area that doesn’t get wet.

For long-term storage, you can cover it with a tarp or store it in a shed with ventilation.

How Can You Tell If Mulch Is Bad?

There are a few signs to look out for to tell if your mulch has gone bad.

1 – The Mulch is Sour-Smelling

Mulch should have an earthy or woody smell. If you sniff it and it smells like vinegar, ammonia, or sulfur, you have bad mulch.

This often happens if you store mulch in piles that are too large. There’s no ventilation, and the middle area doesn’t get oxygen.

Because of this, the mulch starts to ferment and smell bad. Unfortunately, sour mulch is toxic to plants.

The effects are bleached, scorched, and falling leaves. In some cases, it can even kill the plant.

Testing for Sour Mulch

It’s possible to test for sour mulch using a pH meter. Soak the mulch in distilled water and check the pH.

Don’t use mulch with a pH of 1.8 to 2.5.

How to Fix Sour Mulch

You can try spreading the mulch out and exposing it to sunlight. This’ll allow the organic acids to evaporate within a week.

Other gardeners use limestone to neutralize the acidity. You may also try washing the toxins off with water.

Never store your mulch in piles higher than four feet, and turn the mulch over frequently!

2 – It’s Too Dry

If you let mulch get too dry, it could make it hydrophobic or water-repellent. Hyper-dry mulch is clumpy and petrified.

You can tell the mulch is too dry if it’s difficult to scatter.

When mulch is like this, it may not let water pass through to the soil. Because of this, dry mulch can kill your plants!

How to Fix Dry Mulch

You should always check the moisture of your mulch. If it seems compact you should fluff it up with a fork.

Ensure that water is channeling into the soil, and avoid applying the mulch too close to your plants.

3 – The Mulch Has Mold and Fungi

Moldy mulch happens when there’s too much moisture. The excess water makes it an ideal breeding ground for mold and fungi.

Although moldy mulch isn’t bad for your plants, it could cause stains on your property. The artillery fungus, for instance, can release spores that’ll stick to your house or car.

Toadstool mushrooms can also be poisonous to you and your pets.

How to Fix Moldy Mulch

Mold and fungi often grow on mulch made from fine wood. You can avoid it by buying wooden mulch more than 3/8th of an inch in diameter.

Pine and cypress wood are more resistant to decay.

You can encourage the growth of beneficial bacteria in your mulch by soaking it in water before use. The beneficial bacteria will prevent the growth of mold.

Moreover, you can mix grass clippings and manure into the mulch. These will add nitrogen to the mix and cut mold growth.

Final Thoughts

Does mulch go bad? Unfortunately, it does.

Mulch can go bad if you don’t turn it over frequently. It can result in sour mulch that’s deadly to plants.

It’s also possible to make mulch too dry or too wet. The former may turn the mulch hydrophobic, and the latter might develop poisonous fungi.

Luckily, if you store your mulch properly, you can keep it indefinitely.

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