Everything You Need To Know About Potting Soil

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If you are creating a garden, you’ll need to get the right potting soil. This contains all the nutrients that your plants will need to grow strongly. So, what are the more important things to know about potting soil?

Potting soil is designed to be used for garden beds and flower pots. It contains all the nutrients your plants need to survive and will allow drainage. There are multiple types, depending on the type of plants you are growing. But you’ll need to use it quickly. After two years, it will expire and you will need to rejuvenate it.

Potting soil is one of the most basic components of building a thriving garden. Despite this, there are a few misconceptions that can hinder the way that these are used. Keep reading to learn how you can avoid these mistakes and get the most benefit out of your potting soil.

Potting Soil Vs Potting Mix

Let’s start by looking at one of the most confusing areas for many people is the difference between potting soil and potting mix. At first glance, the differences can appear negligible. But there are a few crucial distinctions. This will allow you to pick the right product for your garden.

Potting soil will typically contain some soil. This has been improved with the addition of nutrients, making it more suitable for gardens than the topsoil that is found in the backyard. This will help to encourage plant growth. It also stops the soil from becoming too compacted. This will allow you to improve the drainage in the garden, so the water gets to the roots.

To achieve this, there are a few elements that will be used to make potting soil. These include;

  • Organic materials. These can be things like rice hulls, manure, or earthworm juice. These will be rich in nutrients and make up the bulk of the mix.
  • Inorganic elements, including things like sand. These are to ensure drainage and won’t break down over time.
  • Additives. This includes things like wetting agents. This will increase water retention.
  • Fertilizers. These will boost the number of nutrients in the soil.

On the other hand, the potting mix doesn’t contain any soil. This reduces the chances that it will contain bacterium that lives in the soil, like fungal spores. But it also means that you might be missing out on some important nutrients.

How Long Does Unused Potting Soil Last?

Sometimes, you might have potting soil that has been sitting around for a while. This raises an important question. How long will your potting mix last?

The longer you leave potting soil, the lower the nutrient levels will become. This diminishes the amount of benefit that your plants will get from using it. Often, it will take six months before this process will begin.

Additionally, some of the ingredients in potting soil will begin to break down. The most common example of this is peat moss. This will begin to decompose rapidly. Because of this, it’s best to use potting mix within one to two years of purchasing it.

Can Potting Soil Expire?

It’s best to use fresh potting soil. This will deliver the best benefits for your plants, ensuring the maximum amount of growth. But will it actually expire?

Technically, the answer is no. As we’ll discuss later, there are a few ways that you can try to rejuvenate old potting soil. But potting soil can go bad. This will limit its effectiveness. There are a few signs that this has happened.

The easiest way of finding this is by looking at the expiration date. Not all bags will have this. Even for the ones that do, it’s important to remember that this is a best before date. Because of this, it’s best to use this as a rough guide.

You might notice that the potting soil has developed a bad smell. This is a sign that bacteria have gotten into the bag. This is what is producing the foul odor. You can also open the bag and check for mold. This will often appear as white specks.

Another big problem is that bags of potting soil will attract insects like fungus gnats. These will absorb the nutrients in the soil and use it as a place to lay their eggs.

It’s also possible that the soil will go hard. This can be a major problem. It’s more challenging to get the soil into the pot and plant your seedlings. Even if you do, the hardened soil will have drainage issues. If the water can’t penetrate through the topsoil, it won’t be able to get to the roots.

Extending the Lifespan of Potting Soil

While potting mix will eventually expire, there are a few ways that you can slow this process. Often, this will depend on the way that you are storing it. There are a few tips you can use to do this;

  • Store it in the original bag
  • If you have already opened the bag, try to reseal it. This stops oxygen from getting into the soil.
  • Place the bag into a storage box. This limits oxygen and stops them from spilling everywhere if the bag is torn.
  • Store it in a dry place. Check the potting soil is dry before you store it.

Rejuvenating Expired Potting Soil

If your potting soil has expired, don’t throw it away just yet. There are a few techniques that you can use to rejuvenate it. If this works, you will be able to use it safely in your garden. The way that you will do this depends on why the soil went bad.

If you noticed that there were fungal spores in the soil, you should spread it out on a sunny day. The sunlight will kill the spores. After this, it should be safe to use it in your garden.

If there are insects in your potting soil, you might need to use sticky traps. This will allow you to kill and remove them. However, this might not be a sure-fire plan. Sometimes, there will be too many bugs to give rid of all of them.

Lastly, the soil might have become compacted. This is often because the peat moss has started to break down. In this case, you will need to add coconut coir to the soil. Mix this in on a 1:1 ratio. Finally, add water. This should start to break apart the soil, making it more malleable.

Failure to Revive Potting Soil

While these attempts to rejuvenate your potting soil might have had success, sometimes it will be too far gone to salvage. But it makes no sense to let it go to waste. There are a few ways that you can use expired potting soil.

First, you might want to use it to establish a worm farm. This will bring a range of benefits. First, it can be a good way to dispose of household waste. The castings are high in nutrients. You’ll be able to use this in your garden.

Another option is to use the expired potting mix for compost. Mix it in, add your food scraps. Leave it for a few years. The organisms in the soil will break down the organic matter. Then, you will be left with a highly nutritious mix that can supercharge growth in your garden.

Types of Potting Soil

There are several types of potting soil that you will be able to use, depending on the type of garden you are aiming to foster. The main difference between the potting mixes is the ingredients that they use. The most common varieties are;

  • All-purpose potting soil-As the name suggests, this is a good general potting soil. It should do well in most situations.
  • Seed starting soil-These are designed specifically to provide the conditions that seeds need to grow
  • Moisture control-This is designed to protect against overwatering or underwatering
  • Outdoor potting soil-This variety has been designed to go outside. They usually contain wood pellets, which protect the plants from cold temperatures.
  • Organic potting soil-This is best for plants that you intend to consume.

Often, the most expensive mix won’t be the best. Instead, you’ll need to think about the type of plants that you want to grow. This will inform the type of soil that they will require.

Elements of Potting Soil

There are a few ingredients that will are core to making up the potting soil mix. These include;

  • Peat-This is used because it holds a lot of water
  • Perlite-These look like white pebbles. In reality, though, they are volcanic glass. This helps improve moisture. The heavy shape can help break up the soil, preventing soil compaction.
  • Sand-This exists to improve drainage and can help prevent compaction.
  • Vermiculate- This holds a lot of water. It also contains a lot of nutrients, which it will be able to slowly release over time.
  • Wood Chips-This will improve drainage. As they begin to break down, they can release some nutrients.
  • Rocks-This will assist drainage

The exact mix of ingredients will depend on the mix. By looking at the ingredients list, you should be able to determine how it will affect your garden. This will help you find the right mix for you.

Types of Potting Soil Fertilizer Chemicals

There are two ways that the fertilizer nutrients can be released. You can get the starter soil. This is designed to give your plants all the nutrients they need to start their life. Often, they will have used these up after the first few times you water them.

Alternatively, you can use the slow release version. In this case, the nutrients will last longer. Often, they will be able to last for a few weeks.

Regardless of which version you choose, you will need to add fertilizer eventually. This supplies the nutrients the plants need to continue growing. We’ll discuss how to do this later.

Making Your Own Potting Soil

Sometimes, you might want to create your own potting soil mix. This is relatively easy to do. You’ll just need to purchase the ingredients individually. They should be commonly available at your local hardware store. Then, you’ll need to mix them in.

In this case, you’ll need to use three parts moisture-retaining substances to one part aerating substance. As an example, this can mean using three parts of perlite to every one part of wood chips. You can mix in some compost. This will add the nutrients that plants need to grow.

Using Potting Soil

Once you’ve found the right potting soil for you, it’s time to put it to use. There are a few guidelines you should follow when doing this. The first to understand is where this soil was designed to be used. It’s best to stick to using potting soil in flower pots and raised garden beds.

It’s not recommended that you mix it with the outdoor topsoil. This is because of the way that potting soil could affect drainage. Sometimes potted soil can increase the amount of water that runs off the topsoil. This can make the ground too dry, slowing plant growth.  

Before you add the potting soil to your pots, there are a few things that you should be doing. First, flip the pot over. This will allow you to check if it has drainage holes. If not, you’ll need to add these. You’ll just need a few small holes in the base of the pot. Use a fine mesh to cover these holes. This ensures that the soil stays in the pot, rather than spilling out the bottom.

Next, it’s time to prepare the potting soil. As you are doing this, you can put it into a wheelbarrow. This will make mixing everything a lot easier. First, you’ll want to add soil polymers. These will increase water retention in the soil. You’ll need to use a ratio of one and a half teaspoons of polymers to every gallon of soil.

Next, you can add fertilizer. It’s best to get an even mix. This means that the NPK numbers will all be the same. You won’t need a lot of fertilizer. Half a tablespoon to every gallon of potting soil should be enough to get the right result.

Once this is combined, you can put the mixture into your pot. As you are doing this, you don’t want to fill the pots to the top. After you’ve put the soil in, it will likely expand a little. You don’t want the soil to overflow the pot.

Using Garden Soil in Pots

Sometimes you might be wondering whether or not you need to purchase an expensive potting mix. After all, you have a backyard that contains plenty of dirt. Why can’t you use that in your pots instead? Garden soil can present a few problems.

  • High density. Because of this, there is a big risk that it will begin to get compacted. When this happens, water won’t be able to penetrate through the soil. Without this, the plants will die of thirst.
  • Lack of nutrients
  • Will struggle to support seedlings

Adding Nutrients to Potting Soil

Once you have planted your garden in potting soil, you’ll need to care for it. Most of this will be fairly self-explanatory. You’ll need to water the garden regularly. You’ll also need to make sure that the garden is in the right place. This will give the plants the right amount of sunlight. Every once in a while, you’ll need to remove the weeds.

The potting soil will only have a finite amount of nutrients. Once the plants use them up, their growth might start to slow. Because of this, you will need to keep putting nutrients into the system. There are two ways of doing this.

 First, you’ll be able to add liquid fertilizer. These will be available in most hardware stores. To decide what type of fertilizer you need, you’ll have to measure the NPK in the soil. There should be a simple test that you can use to understand what the soil will need to thrive. Then, you can focus on replenishing the nutrients that the soil lacks.

Usually, this type of fertilizer will appear as small pellets. You’ll need to mix this with water. Then, you pour this over the garden.

The second option is to try to create nutrient-dense substances yourself. There are plenty of ways that you can do this. For example, you might want to start a compost heap. Or you can grow a worm farm. You’ll be able to use the castings to fertilize your garden. These don’t cost a lot to implement, but they will provide a steady supply of organic garden fertilizer.

Final Thoughts

Potting soil should be used when you are growing plants in a pot or garden beds. This can be a good way of making sure that your plants have all the nutrients they need to grow. While it will expire over time, there are plenty of ways to get it into a useable state. There are plenty of types of potting soil. This will make it easy to find the right one for your garden. Then, all you need to do is mix it up and apply it to your garden.