Soil is composed of organic and inorganic material, along with minerals, gases, and liquids. There are all kinds of things that can be found in soil, such as rocks, sand, clay, leaves, sticks, etc.
But what makes the best potting soil?
You can’t go out and dig up the soil in your yard and put it in a pot because those ingredients, many of which is listed above, will eventually turn into a brick under the pressure and heat of a container.
The best potting soil will have three basic elements, then a few other things for certain plants, but let’s not get ahead of ourselves. The three basic elements are:
- The best potting soil will be free draining and water will not stand idle in it. Straight peat moss is not used because it creates a bog effect by holding so much water.
- The best potting soil will be able to maintain at least a little bit of moisture. Sand does not hold any water and is dry within minutes.
- The best potting soil will be strong enough to support the plant. Perlite by itself would not be able to support the stem of a plant in the slightest breeze, it would blow over.
These three basic elements are just examples of what can not be used by themselves, but with certain combinations, these and many other ingredients will make the best potting soil ever for use with certain plants and applications.
Best Potting Soils for Raised Beds
For plants to really thrive they like loose soil so the roots can move about freely. If you have gone through the trouble of creating a raised bed, you more than likely have bad garden soil, so then you will want to use something that is better than your native soil.
#2 Miracle-Gro Raised Bed Soil
Main Ingredients: Sphagnum peat moss, compost, and Poultry litter which is a blend of organic waste produced from chickens like manure, uneaten corn feed, shed feathers, and pine shavings which are often used as bedding materials. It also contains hardwood shavings and bone meal.
Ideal for: Flowers, Fruit, Vegetables, Herbs
This product is ideal because it is easy to use and pre-packaged. The peat moss will retain some water, the bone meal will add calcium as well as some drainage. The hardwoods also add drainage. The compost and poultry litter add fertilizer so little must be added later.
#1 Espoma Organic Potting Mix
Main Ingredients: sphagnum peat moss, limestone to help with the pH, worm castings, alfalfa, shrimp, and kelp meals as well as perlite.
Ideal for: All indoor and outdoor container plants (including vegetables, fruits, herbs, and flowers)
While many of the same ingredients are listed for this and my number two best potting soil for raised beds, the Espoma product comes with Myco-Tone Mycorrhizae. Mycorrhizas create associations between the plant roots and beneficial fungi. This potting mix has perlite for drainage as well as the different manure and meals that provide nutrients.
Best Potting Soil for Container Growing
Best Potting Soil for Citrus Trees, Succulents & Cacti
If you are a conventional thinker, you would never put these three plants in the same category to be using the same type of soil. But hear me out, it will make sense in a moment. I have two favorites here again, and I will start with #2.
#2 Miracle-Gro Cactus, Palm & Citrus Mix.
Main Ingredients: Sphagnum peat moss, composted forest products, sand and perlite
Does contain Miracle-Gro Plant Food for added nutrition
Ideal for: Cactus, Palm & Citrus.
This formula comes equipped with the three basic elements I mentioned above, and the sand and perlite help prevent soil compaction.
#1 Espoma Organic Cactus Mix
Even though this one is called Organic Cactus Mix, the sub-heading lists palms and citrus.
Main Ingredients: Sphagnum peat moss, sand, earthworm castings, limestone, and perlite
Ideal for: Cactus, Palm & Citrus.
While this one also lists all three of my basic elements, it has the added worm castings and Myco-Tone Mycorrhizae. It is my favorite to use in the ready-made category. Worm castings add an extra element of fertilizer and the Myco-Tone aids in root development.
Best Potting Soil for Orchids
Orchids are a slightly different breed of plants than we have discussed so far. You can’t treat them like any other houseplant. If you want the fastest way to kill an orchid plant it in normal potting soil. The orchid mix is a blend of large chunk like ingredients.
The most important things to remember when it comes to the mix for orchids is aeration and drainage. Orchids do love moisture, however, they do not need it constantly. They do not have the same type of roots that other houseplants have. If orchid roots are left in water for any length of time, they will develop rot.
#2 Better Grow Special Orchid Mix
This stuff was created by some highly trained and expert orchid growers.
Main Ingredients: western fir bark, hardwood charcoal, and sponge rock
It is a multi-purpose potting mixture
Ideal for: any kind of orchids, such as cattleyas, phalaenopsis, dendrobiums, oncidiums and any of the epiphytic orchids
This mix gives you the drainage you need as well as allowing excellent root ventilation. I list it as #2 because the couple of packages I have actually bought the pieces seemed a little big for my pots, I had very small plants. I dug through the bag and used what I could and that worked fine.
#1 Espoma Organic Orchid Mix
Main Ingredients: Western Fir Bark, Perlite & Horticultural Charcoal
Ideal for: all orchids and bromeliads.
You can never go wrong with the Espoma products. This mix is organic and will aid in drainage and aeration. The sizes of the pieces were much more consistent in the bag(s) that I have bought.
The Best Potting soil is more than likely one that you will make yourself!
What is the perfect mix? That depends. Every gardener has his or her own “secret” recipe. What works for one, might not work for another. There are so many factors in play. The type of plant, get to know what your plant really needs, extra aeration, moisture, etc. Then take into account your atmospheric conditions, your ability to keep up on the plant’s needs, so forth and so on. You also have to think about the availability of ingredients. Some things are just not available in certain parts of the world, use what you have.
Most experts agree that a good container potting soil should be lightweight, drain well, and contain enough organic matter to hold moisture and nutrients through any kind of weather.
Use the above-premixed soils, see how they do in your conditions, then play around with them by adding things to accommodate any issues that arise.