How To Tell If Your Potting Soil Is Bad - Backyard Boss
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How To Tell If Your Potting Soil Is Bad

Have you ever wondered if potting soil can go bad? Moreover, is it something that you can fix? The quick answer to both these questions is “Yes.” The older potting soil gets, the fewer nutrients it has due to certain ingredients, such as peat moss, decomposing. In this article, you’ll learn how to tell if you have bad potting soil, what happens if you use it, and how to revive it if you do.

Does Potting Soil Go Bad and How to Tell

Your potting soil can definitely go bad if you don’t store it properly or don’t use it for a long time. This is because most potting soil contains organic ingredients that decompose as time goes by. This process causes the soil to lose its aeration and lower its water retention capacity, which will make it dangerous to any plant.

Moreover, salts from the mineral and fertilizer deposits will get caught in the soil. This can lead to the plant roots getting burnt. But how can you understand whether your potting soil has gone bad? Well, there are five main ways to tell if it has:

1. Compaction

Spring Houseplant Care, repotting houseplants. Waking Up Indoor Plants for Spring. Woman is transplanting plant into new pot at home. Gardener transplant plant Spathiphyllum
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Tightly packed or heavy soil is usually a good indication that there’s a problem. It is primarily a issue with old soil and mixes containing peat moss. Peat moss is only viable for about two years, so when it decompresses, the soil becomes very dense. To fix this, you will need to remove your plant from its container and mix it with new potting soil. You must also add wetting agents — this way, the surface tension of the soil will decrease and water will absorb into the soil more easily.

2. Bad Smell

washing soil
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When the soil is old and damp, anaerobic bacteria start to grow. This will result in a foul smell similar to that of rotten eggs. The best way to deal with this issue is to spread the soil in a thin layer on a tarp and let it dry. Remember, though you can reuse this soil, you will have to mix it with new potting soil because the sun will have killed all bacteria, both useful and harmful.

3. Mold

White mold on soil in flower pot
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Mold is another sign that something has gone wrong. It usually occurs when damp soil is stored in closed containers for a long time, especially during the hot seasons. Moldy soil will cause root rot in potted plants. One way to deal with this is to spread the soil out in the sun and let it dry out well. Once this is done, you should store it in an airtight container before use. While mature plants can live in moldy soil for a little bit, seedlings and young plants won’t survive.

4. Insects

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If you see insects, such as gnats, this means that your soil is not good. Gnats eat decomposing matter, thus depleting nutrients and harming the roots of the plants. In order to end the infestation, you should get rid of gnats by using diluted neem oil or even sticky traps. Once you’ve done away with the gnats, you can safely reuse this soil.

5. Changes in Your plants

improper watering makes leaves yellow
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Last but not least, one of the most obvious signs that you have a problem with your soil is the changes you can see in your plants, such as change in leaf color, leaves falling off, or lowered yield. This usually means your plants aren’t receiving the nutrients they need. You can fix this by adding fertilizer to your potting soil. You should usually go for a fertiziler with a higher nitrogen level, but depending on the plant, you may want a different type of fertilizer.

How to Revive Old Potting Soil

When your old potting soil is bad, you can learn how to refresh it, as it can still be salvaged and nurtured back to health. Here are some tricks to try:

1. Fresh Soil Mixture

hands holding soil
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Mixing old potting soil with fresh is one of the easiest ways to revive your potting soil. All you have to do is create a 1:1 ratio mix. While creating your own fresh potting soil is easy, depending on the ingredients of the fresh potting soil, it will take a long time and the results may not be the best in this case. This is because if you accidentally mix old and disease-infested potting soil with fresh, the new one will also need to be remedied before use.

2. Add More Nutrients

Hands in Gloves Holding Potting Soil
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If there’s no way for you to get fresh potting soil, you can simply add some compost. This will help replenish the soil with nutrients. You can do a compost to soil ratio of 1:4 or 1:2.

3. Compost the Soil

misting and bedding compost bin
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If you don’t feel like using your old soil, you can always compost it. Adding the soil to your compost pile will help break down other organic material much faster. Moreover, it will keep the insects at bay. However, you must remember that the old soil should only be 10 percent of the compost material.

4. Add Water

Watering Your Compost
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If the soil is old, but hasn’t become compacted yet, you should add water to the pot and let it drain. This will help leach out mineral and fertilizer deposits. However, do not completely soak the pot, because this will cause root rot.

What Are the Characteristics of Good Potting Soil

So, how do we tell if our potting soil is good, you may ask. There are a few traits that will determine that:

  • Lightweight with good soil aeration.
  • Good water drainage.
  • Rich in nutrients such as phosphorus and nitrogen.
  • Full of microbes for nutrient availability.

In Summary

Potting soil can and will go bad if not stored properly. There are a few telltale signs it has, including changes in your plants, unpleasant odor, mold, clumped-up soil, and insect infestations. However, all is not lost, for there are many ways you can bring your old potting soil back to life.

Hopefully, this article helped you deal with potting soil gone bad! Please leave a comment down below if you have any questions and don’t forget to share this article with your friends and family.

Happy Gardening!