Why Reusing Garden Soil In Pots Can Harm Your Plants - Backyard Boss
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Why Reusing Garden Soil In Pots Can Harm Your Plants

Gardening is a wonderful hobby that helps with relaxation and peace of mind. However, sometimes, especially at the start of the growing season, it can become quite expensive. Many gardeners believe that by reusing garden soil in their pots, they’re not only saving up on soil costs but also helping the environment.

Although that is partially true, by reusing garden soil in your pots, you’re putting your plants in harm’s way. Garden soil isn’t the same as potting soil, so it’s easy to think that it can be used the same way, so make sure you understand the difference between these two soils.

Why Shouldn’t We Reuse Garden Soil in Pots?

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Use garden soil outside. It is typically a combination of clay, loam, and sand and contains compost and manure, which enrich it. Garden soil is rich in many nutrients and is very easily accessible, which makes it a favorite for a lot of gardeners.

However, there are a few ways in which reused garden soil will harm your plants in the long run. Using garden soil in your pots is less than ideal because it usually dries out quicker, and you may end up with compacted soil in your pots. This is, of course, quite bad since your plant roots will struggle and won’t have access to the much-needed nutrients.

1. Nutrient Deficiency

Man holding potting soil in his hands
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Using garden soil for potted flowers will lead to nutrient deficits. One of the biggest downsides to using garden soil in pots is that generally, the pH levels of garden soil are not suitable for potted plants. It will lead to severe nutrient deficiencies, which will lead to issues for your plant’s health and may even lead to its demise. Here’s how to test your garden soil to ensure you’re not harming your plants.

2. Lack of Sterility

dry sand
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Using garden soil for potted plants may lead to bacterial and fungal issues. As we’ve mentioned before, a big drawback to garden soil is that it is not sterile. This means that it may contain fungi or bacteria that are harmful to your plant. In such cases, the plants are usually on the losing side and may die. However, there is one trick that you can use, in case you don’t have a choice but to put garden soil in your pots. You can make it sterile by cooking it in the oven for a while. This will cause a much lower amount of bacteria and a bigger chance of your plant flourishing.

How to Sterilize Soil

In An Oven

To sterilize in an oven, you’ll need a baking tray large enough to place 10 cm of soil. Cover it with foil and stick a meat or candy thermometer to check the temperature. Bake for 30 minutes or until the soil is 180 degrees F (82 degrees C). Don’t let the soil bake for more than 180 degrees F, otherwise, it will start releasing toxins. Remove from oven, let it cool, but keep it covered with foil until it’s ready for use.

With Hot Water

If you have no access to an oven or a large oven-safe tray, you can sterilize your soil with boiling water too. Place the sand in a large bucket and pour boiling water enough to cover and saturate it. Mix and cover the top of the bucket with foil or a metal lid to maintain and retain the heat inside the bucket. Leave it aside for 30 minutes before use. Remember to let the soil cool before using it in pots. Hot sand can damage your plants.

3. Lack of Density

checking soil moisture
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Garden soil density is not ideal for the healthy growth of potted plants. While garden soil density will not affect outdoor plants at all, it is often too dense to be used in pots. This can lead to water drainage issues, causing root rot, which will quickly travel up to the stem of the plant. You can learn how to identify and prevent root rot to save your plants from dying. Also, because of the density, you may have issues with aeration, which will surely have a quick negative effect on your plants.

This is why you should probably invest in the best potting soil for container plants that will surely get the job done, rather than have to spend double the money to fix the issues garden soil created. Gardening Know How has explained in detail why the density of the garden soil will be problematic for potted plants. You should also take a look if you are wondering what other alternatives you have.

What If You Accidentally use Garden Soil for Your Potted Plants?

There’s no doubt that garden soil has its benefits and can have a very high quality, but it is not the same as a specialized potting mix. However, if you accidentally use garden soil from your yard, you shouldn’t panic. There’s a fix for that too!

You will need to mix the garden soil with peat moss and perlite. If you haven’t added compost to your garden yet, you will need to add this too. Mix it all in a 1:1:1 ratio. That is 1 gallon of perlite, 1 gallon of peat moss, and 1 gallon of soil all mixed. This way, you will have your own homemade, high-quality potting mix.

Of course, depending on the amount of potting mix you will need, the measurements will vary. Here’s a detailed guide to help you learn how to make your homemade potting soil for your container plants.

What Soil or Mix to Use for Your Potted Plants?

how much hydrogen peroxide for plants
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Potting mixes are made specifically to meet the needs of potted plants. They are lightweight, provide good aeration, and have a great balance between water retention and water drainage. This is especially beneficial for the plant’s roots. This is one of the most important differences between garden soil and potting mix. Potting mixes are ideal for most plants, except for orchids, succulents, and cacti. If you are looking to take care of these, you should look for specialty mixes.

While the contents of potting mixes may vary depending on what you grow, there are a few characteristics to them. They are lightweight, dry, and fluffy and usually contain peat, bark, perlite, vermiculite, or coir. If you aren’t sure which one would be the best for you, choose a peat-based all-purpose mix, or make one yourself following the steps listed above.

Popular Potting Mixes on the Market

One of the top contenders for best all-purpose potting mixes would be Miracle-Gro. They have a wide selection of products dedicated to all types of potted plants. If you are looking to grow flowers, then you should go for their Houseplant Potting Mix. However, if you want to grow cacti, succulents, and other more exotic plants, worry not! 

They have the Cactus, Succulent & Bonsai Mix. Both are reasonably priced and have received a lot of positive reviews from their users. If you’d like more choices, here’s a product collection of the best potting mix for container plants.

In Summary

While straight garden soil can be a very budget-friendly and organic solution to finding soil for your potted plants, it is a terrible idea. Garden soil is simply too heavy and dense, doesn’t allow for proper water drainage and aeration, and can lead to many problems in the roots of your plants.

This is why you should only use it if you have no other choice, or want to make your potting mix, as we described above. Garden soil is great for outdoors in-the-ground planting, but when it comes to container gardens, whether indoor or outdoor, garden soil should be the last resort.

We recommend you to look at your local store and choose a good potting mix from there. 

Our personal all-purpose favorite is the Miracle Gro Houseplant Potting Mix, whereas the specialty one is the Miracle Gro Cactus, Succulent & Bonsai Mix. Hopefully, this article was helpful to you. Leave a comment in the comment section down below if you have any questions or uncertainties!

Happy Planting!