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What to Consider | Plant Location | Plant Type | The Choice

Choosing the right Potting Soil mix for your container garden is not all that difficult, when you know how. Better still, manufacturers have created Potting Soil blends designed to meet your specific container garden needs. For example, blends optimized for indoor or outdoor container gardens.

This article will carefully take you through what you need to know. You will learn how to choose the best Potting Soil for your container garden, for every plant your growing. You might even discover you need more than one type of Potting Soil so you can meet the needs of your plants.

What to Consider When Choosing a Potting Soil

There are 3 simple things you need to consider before selecting a Potting Soil Mix.

1. Where are my plants located (indoors or outdoors)?
2. What types of plants do I have?
3. What are my plants’ moisture needs?

Answering these 3 questions will give you the best insight into what Potting Soil blends you should consider. Manufacturers create blends that are designed to cater for most environments, plant types, and moisture requirements. By understanding what you need, you can reduce the Potting Soil options available to be just those that meet your needs. You may even decide that more than 1 Potting Soil type is needed. Let’s dive deeper into the detail.

Where is My Plant Located

Where do you keep your potted plants? If you’re like me, you have some indoors and some outdoors. This means you might need a different blend of Potting Soil for each group of plants.

Indoor plants tend to dry out more slowly than outdoor plants. They have less direct sun and little to no wind drying the Potting Soil. Outdoor plants have both wind and sun constantly taking their share of any moisture present in your Potting Soil.

Keeping your plant type in the back of your mind, it follows that your outdoor plants might need a Potting Soil that has ingredients designed to better retain moisture. We’ll discuss which ingredients perform this task below.

What Types of Plants Do You Have in Your Container Garden

Many plants will grow well in an All-purpose Potting Soil. If you want a safe choice, this is a good choice for general use with indoor and outdoor potted plants.

All-purpose Potting Soils tend to have manufactured fertilizers included in the blend to help nourish your plant. If you are planting and growing herbs, fruit, and vegetables, anything you plan to eat, you may choose an Organic Potting Soil. With an organic option, you will need to fertilize regularly yourself. The nice thing here is, you get to choose what fertilizer is added. Whether organic or not, All-purpose Potting Soil tends to have a rich consistency and good moisture retention.

You can be very specific with your Potting Soil choice. For example, Citrus trees like a light weight, slightly acid, free draining blend. Cacti and succulent plants need fast-draining soil with just a bit of organic matter. Some plants dislike wet feet (wet roots) so choose a Potting Soil blended designed to be free draining. By knowing your plant well, you can choose a Potting Soil specifically made for that plant type.

The message here is, know what each plant in your container garden likes. It might mean you need several Potting Soil blends to cover your requirements. Equally, you might be covered with a good quality All-purpose mix if you’re lucky.

TIP
These are our picks for best All-purpose Potting Soils

Potting Soil Components

You should become familiar with what’s in your Potting Soil blend. Potting soil does not actually contain any garden soil. It is a manufactured blend of organic and mineral ingredients. The ratio of these ingredients and other additives like bark and fertilizers help to make each product suitable for a different purpose.

Basic Ingredients

As we covered earlier, Potting Soil does not actually contain any garden soil. Potting Soil is generally made by blending Peat Moss and Perlite or Sawdust/Bark.

Peat Moss is the dead moss and other organic material (leaves and alike) that collects at the bottom of bogs. Over the years, we’re talking hundreds of years, layers build and get compressed to create Peat. Peat is a wonderful thing, it’s all natural, it’s highly absorbent, and it’s naturally resistant to decay.

Perlite is a type of volcanic rock that’s mined and crushed into grit. The grit is then super-heated which makes it expand like popcorn to many times its original size. The resulting Perlite product has an open structure, that allows water and air to circulate freely. This promotes drainage and the movement of air in the Potting Soil mix.

Sawdust and Bark, byproducts of lumber milling, is an alternative to Perlite. These materials add density, richness, and improved moisture retention.

Nutrients

Potting Soil manufacturers list nutrients on the product label. They’re presented as a ratio of percentages in the order of the N-P-K (Nitrogen-Phosphorus-Potassium) content. Nutrients can come from either chemical or organic origin. The nutrients can last from a few weeks to a few months, however over time they will run out. Over the life of the plant, additional fertilization will be required. It’s up to you to choose what type of fertilizer you add.

This section is really all about your plant location and your fertilizer preference. I know many people who grow outdoors and use manufactured fertilizers. Either approach is fine. Having a healthy plant is the most important thing.

Moisture Control

Understanding the moisture needs for each of your plants is important. I know it’s obvious but I’ll say it anyway, different plant have different moisture requirements. Too much or tool little moisture and you will have problems. Most potting soils will have an ingredient designed to retain water, blended in a ratio design to meet the needs of specific plant types. Peat moss, Coco Coir, Sawdust, Bark and even water holding Polymer can be added to the Potting Soil blend to help with this task. All of these materials (excluding polymer) make good base materials, but your plants need a balance to ensure that excess water drains away. Perlite helps provide this balance in the blend. You need to understand the amount of moisture you need retained for a healthy plant. For example, Cactus likes a free draining soil and so we need a blend with a higher Perlite content.

Fungal Growth

Fungus and some molds are wonderful things, they work with bacteria to breakdown items in the soil and release nutrients for your plant. When you first purchase a bag of sterile Potting Soil, it doesn’t contain fungal spores. Over time, spores that naturally live in the air will land on and inhabit your Potting Soil. This is a great thing!

Organic Potting Soils often already include beneficial fungi and bacteria.

Fertilizer

As mentioned earlier, all the plants in your container garden will eventually need fertilizing. Some Potting Soil blends come with fertilizer included, so it’s important to read the label and find out how long this is expected to last. When it’s time to fertilize you can use either or both of the following strategies: nourish the plant or nourish the soil.

Nourish the plant directly by using conventional manufactured fertilizers. These are absorbed directly into the plant roots as they slowly dissolve into the moisture present in the Potting Soil. Manufactured formulations are great in conditions where the grower doesn’t want to have fungal growth or other microorganisms present. This approach is popular with indoor plants.

Nourishing the potting soil is an approach used by gardeners who want to replicate the natural way that plants receive nutrients in the wild. Organic nutrients come from compost, manure, and other natural sources. These resources need to be broken down by bacteria and fungi present in the Potting Soil before the nutrients are available for the plant. Visible fungi and smells make this approach more popular for the outdoor container gardener.

The Choice

So now you’ve learned a whole lot about Potting Soil, and you have a simple way to approach making the right choice.

1. Where is my plant located (indoors or outdoors)?
2. What types of plants do I have?
3. What are my plants’ moisture needs?

When you can answer these questions (for each plant), you can easily find a Potting Soil blend that meets your requirements. In reality you can handle fertilizing yourself, however if it comes with some in the blend, then that’s a nice addition.

Conclusion

I hope all the pieces of this puzzle have now come together in your mind. When you know the Plant Type, the plant location, and the plant’s moisture requirements, you can choose the correct Potting Soil for the job every time. Does my plant like to be damp or dry? Will my plant be indoors or outdoors? Does my plant like rich or free draining soil? Now that you know what makes up a Potting Soil blend you can narrow your focus to blends that will be correct for the plants in your container garden. And if you’re very lucky, an All-purpose blend might be all you need.

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