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Can You Still Use Year Old Mulch? The Facts Explained

Can You Still Use Year Old Mulch? The Facts Explained

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Willie Moore
Latest posts by Willie Moore (see all)

Mulching is a great way to make plants healthier and improve the soil. However, you can also make many mistakes while mulching, so it may end up doing more harm than good. For example, is using year-old mulch a bad idea for gardening?

You can still use year-old mulch as long as it is stored properly and has not gone bad. However, if the mulch has gone bad, it can cause damage to plants. Leftover mulch from the previous season can be used if it has maintained its original feel.

In the rest of this article, I’ll explain when you can use year-old mulch, how to tell if mulch has gone bad, what to do with unusable mulch, and how to make your own. If you’re a gardening enthusiast who wants to be better at mulching, keep reading!

Is Year-Old Mulch Usable?

Year-old mulch is usable as long as it was bagged and stored properly and has not gone bad. You can reuse the mulch you used the previous season if it has retained its original look and feel and has not decomposed too much.

Bagged mulch (which is typically bark) can stay good for a year, but only if it’s stored properly. Ventilation is essential to maintaining your mulch’s health, as oxygen slows down the decomposition process.

If the bag your mulch came in doesn’t have any air holes, poke the bag to make some yourself. You can use a plastic container with ventilation holes for even better results. For the best results, spread the mulch out on a tarp and store it in a dry area.

If you’re going to use a tarp, I recommend something like the Tarpco Safety Tarp Cover (link to Amazon). This tarp is used with tear-resistant material and has reinforced edges, so it will likely last you a long time. Additionally, it’s UV resistant, waterproof, and weatherproof, so it can endure whatever you put it through. 

If you have year-old mulch that you left on top of an annual plant bed, you may be wondering what to do with it or if you can reuse it. Typically, annual plants are mulched in the fall to protect them from harsh winter conditions, and if the mulch hasn’t decomposed too much by the spring, you can still use it.

If the mulch has decomposed too much, it will likely not be distinguishable from dirt because it has broken down into fine particles. In this case, it’s no longer as effective as mulch and should be replaced.

However, if it still looks and feels like it did when you originally used it, you can likely use it again. To reuse, rake the mulch out of the way while you apply compost to the plant bed, then put the mulch back on.

How To Tell if Mulch Is Bad

You can look out for several signs to determine if your mulch has gone bad. Here are some signs of spoilt mulch:

  • The mulch is infected with insects. Sometimes, pesky insects get into even the best storage places. If you notice bugs crawling all over your mulch, it’s probably best to throw the mulch away and buy a new bag. I like Scotts Growing Color Enhanced Mulch (link to Amazon) because it prevents weeds and retains soil moisture.
  • The mulch is infected with mold or fungus. Mulch is susceptible to growing slime mold, which initially appears as a bright color but dries and turns brown. Mulch can also grow artillery fungus with spores that look like specks of tar. Luckily, you can easily remove the spores.
  • The mulch smells bad. Sometimes, mulch smells like rotten eggs, vinegar, or sulfur. This occurs when the mulch starts to decompose without access to enough oxygen. You can fix this issue by spreading the mulch into a thin layer and soaking it in water.

Bad mulch can be detrimental to plant health, so it’s essential to ensure the mulch hasn’t gone bad before you use it.

How To Use Old Mulch

If you determine that your mulch is too old or decomposed to use, you can still use it. If the mulch isn’t dyed, you can use it as compost or soil amendment. Soil amendments are various elements you can add to the soil (such as fertilizer and manure) to help improve plant health.

You can also add the old mulch to compost. To make compost, stack all your compostable materials in a compost bin and keep it watered. Microorganisms will then break up the pile and help the materials decompose. 

In addition to old mulch, you can use the following in compost:

Adding this material to your soil can improve its health and fertility, resulting in better harvests and blooms every spring.

If you don’t want to use your old mulch as a soil amendment, you’ll need to bag it up and take it to a waste management facility. If your old mulch has any signs of disease or infestation, you should dispose of it and get new mulch.

For more information, see Compost vs Mulch: Make Sure You Know the Proper Use For Each.

How To Make Mulch

If you don’t want to buy bagged mulch, you can make your own for cheaper using the following materials:

  • Chopped-up branches and pine needles. If you need a wood chipper, you get get something like the Sun Joe Electric Wood Chipper (link to Amazon). This chipper is ideal for turning leaves, twigs, and branches into mulch. I also like that the locking knob prevents the motor from working when the chipper is opened, so it’s safer than other alternatives.
  • Chopped-up leaves. You can use a lawn mower or hedge trimmers to shred your leaves.
  • Grass clippings. Just ensure that your grass is pesticide free before you use the grass as mulch.
  • Straw
  • Aged compost
  • Torn-up, damp newspaper

Making your own mulch can help save you time and money if your year-old mulch is unusable.


Proper mulching provides many health benefits to plants, trees, and shrubs, but if you use mulch that has gone bad, you can cause your plants some serious problems. Typically, it’s okay to use year-old bagged mulch if it has been stored properly and hasn’t gone bad. You can also reuse the mulch you used the previous season if it retains its original look and feel.

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