Choosing potting soil for container gardening doesn’t need to be difficult. In this post, I’ll talk about the different types of soils, and show you which ones to avoid. You’ll also learn what to look for in quality soil for planters, so you’re sure to pick the best potting mix for container gardening every time!
One of the biggest challenges of growing in pots is the fact that the soil can’t regenerate or gain any extra nutrients from the earth. And the roots of a container grown plant can’t sprawl out or go deeper into the soil to get what it needs.
Plants growing in pots depend completely on us to give them what they need to survive. That’s why it’s super important to choose the best soil for container gardening.
But how can you tell which one is the best? Below, I’ll give you tons of tips for choosing soil for containers, and which ones to avoid. In the end, you’ll feel confident that you’re using the absolute best soil for planters and pots that you can.
Choosing Potting Soil For Container Gardening
Soil is the foundation for growing healthy plants, so it’s very important that you always use high quality soil for container plants.
Never cheap out on potting soil for container gardening, because you really do get what you pay for here. If you start with a good mix, your plants will grow much better.
It may be a bit more expensive to buy, but a quality container soil mix makes all the different in the world!
Different Types Of Container Gardening Soil
If you’ve ever walked down the soil isle at your local garden center or home improvement store, you know that there are tons of options to choose from.
But why are there so many kinds of dirt? And how the heck do you know which one is best for your containers? I mean, dirt is dirt, right? Nope.
Though you’ll see tons of different types of dirt, they are definitely not all the same. Things like cheap fill dirt, topsoil, and garden soil are not good to use in your pots.
In addition, there are different types of soil for container gardening formulated for specific purposes. Some are best for growing flowers and ornamental plants. While others are made for growing container vegetables and other edible plants, for example.
Can I Use Garden Soil In Pots?
Many new gardeners make the mistake of using garden soil in pots. I mean, your plants grow great in your garden, so why wouldn’t that same soil work in containers too?
You might get lucky and have no problems at all. But… you’re taking a BIG risk if you use garden soil in containers. This is a bad idea for several reasons.
First, garden soil has lots of potentially nasty stuff in it, like bugs and other creatures, disease organisms, and weed seeds. Put all of those yuckies into a container, and you’re just asking for trouble.
Plus, garden soil is too heavy for use in containers, and will quickly become compacted in there. When that happens, it’s extremely difficult for the plants to grow.
So it’s best to leave the garden soil in the garden, and use potting soil for containers to ensure your plants will grow and thrive.
What Is The Best Soil For Container Gardening?
Choosing the best soil for outdoor potted plants is important, but it doesn’t have to be intimidating. First, be sure to always read the label to see if the soil was created for a specific purpose.
For most outdoor plants, choosing a good quality, all-purpose soil mix for containers is usually the best option.
If possible, open the bag to check the consistency of the container garden soil mix before you buy it. Like I said above, they aren’t all created equal, and companies have their own formula.
So, it’s best to check to see for yourself. Here are some things to look for in a quality potting mix for containers…
- the medium is light and fluffy
- it has good drainage, but also holds moisture
- it’s porous so that water and air can easily reach the roots of the plants
- there aren’t any weed seeds germinating in the bag, or tiny bugs flying around it
- there’s not a large amount of bark or sand in the mix
- it’s moist but not soggy, and the smell is pleasant
Best Soil For Large Planters
Before deciding which soil to use in container gardens, think about where you want to put your plants. You don’t need to worry about the weight of pots that will be sitting on the ground, but you do for hanging planters.
Soil and compost mixes are heavier, but are perfect for use in pots sitting on the ground. So in this case, choose a general-purpose container plants soil mix. These mixes usually contain compost.
Best Soil For Planter Boxes & Hanging Baskets
When you grow plants in hanging baskets and planter boxes, you have to think about the weight of the containers. It’s amazing how heavy a pot will become once it’s filled with soil and saturated with water.
Learn more, and find out how to make potting soil for containers (with recipes) here.
Can I Reuse Soil For Containers?
Most of the time the answer to this question is no. You don’t want to reuse soil in your containers for two main reasons.
- It could be contaminated with disease spores or bugs from the previous year which can infect the new plants
- The soil will be stripped of its nutrients, or completely filled with roots from the plants that grew in there before
So, it’s best to dump the used garden pot soil into the compost bin, and start with fresh, sterile soil every year. That way, you’ll ensure your plants will grow their best.
However, if you have extremely large and deep containers or planter boxes, then you don’t need to replace all of the soil. In this case, I recommend removing the top 3-5 inches, and replacing it fresh soil before you plant anything new in there.
How Much Potting Soil For A Container
The amount of soil you need for each of your pots will depend on the size of the container. It can also vary depending on the number and size of the plants that you’re putting in there.
Check the label before purchasing your container gardening soil mix. It should tell you exactly how many bags you’ll need based on the size and number of containers you’re planting.
How To Fill Soil In Your Pots
Before you begin filling your containers, always be sure to start with clean pots. Dirty containers can harbor disease and pests, and you don’t want to risk it.
So, if you’re reusing a container, simply use a flower pot brush to remove all the crusted on dirt. Then wash the pot with soap and water to clean it.
To fill your pots, add some container garden mix into the bottom, and lightly pack it down. You want to fill the pot just enough so that when you set the rootball on top of the soil, the plant will be at the correct depth.
Plan to leave about an inch of space between the soil and the top of the container once it’s filled. That will allow the water to soak in rather than running over the top, which makes a mess and deprives your plants.
Next, hold the plant in place and fill in around the roots, lightly packing the soil as you work. Be sure the rootball is planted at the same depth as it was in the original pot.
Do I Need To Add Fertilizer To Container Potting Mix?
Container potting soil loses it’s nutrients much faster than soil in the ground. The plants use up the nutrients as they grow, and more are flushed out the bottom of the pot each time you water.
So, it’s important to make sure you feed your outdoor potted plants on a regular basis. After all, they are depending on you to give them the nutrients they need to survive.
This is especially important when you’re growing edible plants because they need tons of nutrients in order to produce all that yummy food for us!
Best Fertilizer To Add To Container Gardening Soil
I highly recommend using an organic granular fertilizer when you first plant your containers. Chemical fertilizers can burn the roots of tender plants, which is a big problem in container gardens.
These days there are tons of wonderful options for natural fertilizers, and they are extremely easy to use. I add either an organic vegetable fertilizer, or a general purpose one in all of my containers when I plant them.
You should also use organic liquid fertilizer weekly throughout the summer. My favorites are liquid compost fertilizer tea (which you can get as a concentrate, or buy compost tea bags and brew your own), or a seaweed fertilizer (like this one or this one).
Learn even more about how to fertilize outdoor potted plants and containers here.
Container Garden Soil FAQs
Below I will answer some of the most frequently asked questions about container potting soil for outdoor plants. If you still have questions after reading this article and this FAQ section, then ask them in the comments below. I’ll answer them ASAP.
Can you use manure in containers?
Yes, you can mix manure into your containers, BUT only if it’s well composted. Fresh manure is too strong and can burn the roots of your plants. It can also contain pathogens that could infest your plants, or make you sick. Plus, it probably won’t smell very good.
Can you use compost instead of potting soil?
No, compost alone won’t be a good option. It’s best to use a compost soil mix which contains other ingredients to prevent soil compaction, and improve aeration and drainage.
Can you use topsoil for potted plants?
No! I know it’s much less expensive, but do not make the mistake of using any type of cheap dirt in your containers. Cheap topsoil or fill dirt will not work well in containers because it has no nutrients. It’s just rocks and dirt.
Can you mix topsoil with potting soil?
I would not recommend mixing topsoil into your soil mixture for container gardening either. Again, it’s just a filler dirt and is not meant for growing plants. Topsoil contains no nutrients, and has no benefits for the plants.
Can you mix potting soil with garden soil?
I do not recommend mixing potting soil with garden soil for your containers. See the section above called “Can I Use Garden Soil In Pots?” for more details. If you accidentally used garden soil in pots, then I recommend repotting them into fresh potting soil for containers.
When it comes to growing plants in pots, you always want to be sure to use a high quality soil for container gardening. Remember, soil is the foundation for a healthy container garden. Using the best soil for containers will ensure you will grow beautiful and productive plants.
More Container Gardening Posts
- Container Flower Gardening Design Tips & Ideas
- How To Clean Terracotta Pots (In 3 Easy Steps!)
- How To Install A DIY Drip Irrigation System For Potted Plants
Share your tips for choosing the best potting soil for container gardening in the comments section below.