Soil Mix For Container Gardening

Last updated: 01/18/21

Garden soil is super important for containers, but you may need to add some amendments to it before being used.

I found that, even though my garden soil is stable and rich in nutrients, it still doesn’t do the job right out of the ground.

I need to boost the quality of my soil to help my plants grow big and strong.  You don’t want the roots of your plants to choke or drown from compact lifeless soil.

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Potting soil which can also be called potting mix is a source or medium in which crops like vegetables, herbs are grown in a containing vessel.

Potting soil can either be peat combined with Dolomite limestone-based or can be coir-based. I will explain further both types of potting soil later on.

Types Of Potting Soil

There is a wide variety of potting soil which plants use for specific reasons. For plants to grow strong and healthy, the potting soil must meet the required needs of the plant.

The soil structure also determines how well a plant will develop and grow. The following are some types of potting soil.

Sowing and Propagating Soil

To achieve the right consistency of sowing/propagating soil, the right amount of fertilizer and nutrients must be used. If the soil contains too many nutrients or salts, it can cause harm to the roots of the plant. High amounts of salts in the soil can potentially kill the roots of a plant.

container gardening proper soil mix

The major raw material for sowing and propagating soil is fine coarse sand because it is porous and light. It also doesn’t need to retain a lot of water mainly because it can potentially develop fungus.

To properly germinate a seed with this media, the right composition of air, water, nutrients are required.

Soil For Acidophilic Plants

Acidophilic plants grow better on soils with low pH values. The right potting soil composition for an acidophilic plant includes a mixture of black peat to give the soil a low pH value, and a semi-moist structure.

Box Soil

This soil is reserved for plants that require high pH values to grow successfully. It composes of a high amount of Iron and magnesium iron which is the main source of its high pH.

Cactus Soil


A cactus plant only grows in regions or areas with a high amount of sunlight, warmth, and little water. The right soil composition is a rather important value as it determines how well the cactus will grow and flower.

Important factors of a cactus soil include light in weight, efficiency in drainage, porous soil structure.

Soil for Ferns, Roses, and Anthuriums


Unlike other plants, these specific set of plants require and extra nutritious soil for their plant growth. The best type of soil for these plants is those with a good RHP quality mark.

Pond Soil


This soil contains heavy soil parts that make it stay underwater rather than float at the surface. Plants like water lilies and water mint plants enjoy these conditions and can be found growing on this soil.

Universal Potting Soil


Key elements of soil include Nitrogen, potassium, and phosphorus. This soil tends to have a comfortable balance between these 3 elements, basically, it can be referred to as an all-round soil.

What Is The Difference Between Potting Soil And Regular Soil?

Regular or garden soil is a combination of naturally formulated topsoil or sand and a rather decent amount of bulk organic materials. Potting mix on the other hand has no natural soil in it.

It is a well-reformed mix produced from peat, ground pine bark, and perlite or vermiculite.

How to Make Your Own Potting Soil Mix

Depending on how many containers you use in the garden, making your own garden mix is cheaper than purchasing several bags of pre-made Potting mix.

Making your own potting soil also gives you the freedom to customize the mix for different plant varieties.

However, if you only need a small amount of potting mix for a small garden, it is, however, better if you purchase the mix. It saves you time and energy.

Making your customized potting mix should only or mostly be done for a large scale project or for a long term project.

Before making your own soil mix, you have to consider the following key points:

  • When deciding your mix, the best soil type to make use of is a very light one, the lighter, the better.
  • If the mixture is loose and porous; the containers are easy to move, it transports water, fertilizers, and air to plant roots faster. It also gives the soil good drainage, which is an important element for a good container garden.

How To Make A Homemade Potting Mix

To mix your personal potting soil blend is rather easy, this also gives you total control of the crucial steps in the growing process of your crops. This is important because, for container gardeners, the variety of potting soil used is very important, and it has to be of high-quality.

As earlier said, making your own potting soil gives you better freedom in choosing the specific soil type to use for certain plants. You not only save money but also get better outcomes from the soil you made.

Start by adding one gallon of moist, very coarse sphagnum peat moss to a gallon of either coarse sand, vermiculite, or perlite. If you find the soil is tight, adjust the source or medium for a more loose and drained mixture.

Add more peat moss if the potting mix has too much sand.

mixing soil for container tutorial

Afterward, take a large amount of homemade potting mix and combine in a cement mixer or a compost tumbler for a large scale mixture.

If you want small scale quantities, combine the ingredients with a wheelbarrow, a big bucket, or even a mortar mix tub. Ensure that the ingredients are mixed thoroughly and evenly to give a consistent result.

Best Container Potting Soil Mix Recipe

Soil-based or peat-based potting medium is made by mixing various individual ingredients. I will go over each individual ingredient to give you better insight into what they are before discussing the basic recipe.

Bear in mind, the recipes stated here are measured in gallons for the primary ingredients, and in teaspoon/tablespoon or grams/ounce for the secondary or small ingredients.

Primary Ingredients

Sphagnum Peat Moss

This ingredient has a very coarse texture and gives the mix good aeration. It also makes the soil capable of holding water more effectively to prevent the soil from drying out quickly.

However, using too much sphagnum peat in a mix can reduce soil drainage making the soil hold too much water. This ingredient should first be moistened first before it is mixed with other ingredients because it can be difficult to wet.

Sharp, Coarse, Or Builder Sand

Although it is mostly used in construction, this is the main ingredient for potting medium. Similar to the sphagnum peat moss, coarse sand can because of its loose nature improves drainage and aeration of the soil. It, however, does not help in building the water-holding capacity of the soil.

Having too much sand in your mix can increase the weight of your container. It is also important to not mix sand in clay-based soil.

Perlite

This ingredient can be used in both potting media as a replacement for sand. It has similar features to sand, but is lighter and retains more air when compared to sand.

This ingredient is rather more expensive than sand, which doesn’t change the fact that it is worth the price.

At times, perlite tends to float at the top of the container when watered, it doesn’t hold water well enough, and like peat, needs to be moistened before it can be mixed with other ingredients.

This should be done with care because it is harmful if inhaled.

Vermiculite

This can be used in place of perlite. It is clay-based and belongs to the mica family. It occurs naturally as laminated flakes, vermiculite folds have the ability to retain or hold water, nutrients, and air, a trait that perlite lacks.

However, I advised you to buy horticultural grades which are sold in garden centers. Vermiculite compact too easily, this features inhibits its ability to retain water and air.

Recipe For a Soil-based Potting

Given below is a step by step process/recipe for making a Soil-based Potting media.

In this recipe, coarse sand, sphagnum peat moss, and loamy soil are combined equally in parts by volume.

  1. Start by first pouring a gallon of the garden or sterilized loamy soil into a bushel basket. You make use of sterilized loam soil to prevent diseases, weed, and insect problems that may occur in unsterilized soil.

    Contaminated or unsterilized soils can have future consequences on planted seeds such as deformation, dead, or stunted seedlings. Weeds also tend to grow fast and struggle nutrients, air, light, and water with young seedlings.
  2. Add a gallon of moist, sphagnum peat moss, and a gallon of sand, vermiculite, or perlite.
  3. Create a well-drained, loose mixture by ensuring the texture of the media is well adjusted. Sand has a gritty feel, while the clay is sticky. If you have too much sand in the mix, add more peat, make sure to adjust the texture while mixing until it suits your taste.

Soilless Potting Mix or Peat-Based Medium

A soilless mix or peat-based medium does not contain soil as the name implies. It contains peat mixed with horticultural grades of vermiculite along with/or perlite, and a blend with fertilizer.

A peat-based medium helps in seed germination because of how light in texture they are and their uniform soil mount.

This light texture gives seeds the freedom to grow well, it gives room for the roots to spread well, and because of how to lose it is, makes transplanting of these seedlings easier.

A standard homemade peat or soil mix recipe consists of half amount of sphagnum peat moss and half vermiculite/perlite.

To get a 4-gallon medium result:

  1. Pour 2 gallons of peat moss into the bushel basket.
  2. Mix well with 2 gallons of perlite or vermiculite.
  3. Before putting the mixture in a pot, moisten it first.

Adding Fertilizer To Container Potting Mix

This is highly recommended for container gardens based on Vegetables, flowers, ornaments, and all varieties of this type of Gardening. Fertilizers are a highly essential element for a successful container garden.

It is rather easy to apply on the soil, just make a fertilizer solution by mixing with water and pouring it over the organic soil. This fertilizer is absorbed into the plant roots and it adds the missing nutrients the soil lacked.

No matter how perfect your plant mix is, it will eventually be depleted of vital nutrients as a plant grows, or it will be washed away during watering. This is because, when plants grow, they tend to require more watering and fertilizer.

The Fertility of soil relies strongly on how much nutrients it has, fertilizers go a long way in ensuring these essential nutrients are provided. Depending on how long a plant will spend in its container, adding fertilizer supplements may or may not be necessary.

Clay and other mineral contents in the soil provide both nutrient and water retention to a soil. Therefore, a soil-based mixture is more fertile compared to a soulless-based mix.

If you need to make a soil-based mixture, ensure to adjust the pH according to the soil test results. You can purchase a soil test kit product from your country’s extension stores or a Garden center.

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Final Thoughts

In summary, a planting mix is necessary especially when done for specific plants. It is very crucial that you pay close attention to your seed’s germination process.

Remember, treat your plant like you would a human, if you don’t hurt its feelings by giving it poor soil, it will grow up a Healthy plant and spread its love to you and your society.

Related Questions

Can You Mix Potting Soil With Garden Soil?

It can be mixed for raised beds but not for containers.

What Do You Fill The Bottom Of A Planter With?

You can fill the bottom of the planter with recycled products such as crumbled egg cartons or shredded paper or leaves.

Green Thumb Gardener
soil mix tutorial beginner guide
Jeremy Starke

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