You need only take a quick walk through a nursery or garden center’s soil aisles to see the large selection of bagged soils and potting mixes.
From composts to garden soils, to all-purpose mediums; sometimes seems there’s a soil for every scenario and every type of plant.
So What Are Bagged Soils?
Bagged soils and mixes are usually a mixture of various materials. The combination of materials is designed to enhance the medium in some fashion for the purpose of supporting your plant.
Unlike us, a plant can’t walk to a store to get its nutrients. What it needs to survive, it has to draw from the surrounding soil, air, and water.
So the support the soil offers a plant is very important.
As for the type of support offered, that will depend on the type of soil or mix. For example, some mediums drain better, whereas others may have better aeration. Further still, some are made for containers, others for in-ground gardens.
You get my drift. For the newbie, it can leave you scratching your head and wondering what’s best for your plant.
To help you answer that question, I’ve put together this easy guide on the most common types of bagged soils and mixes, and their uses.
Beginner’s Guide to Bagged Soils & Mixes
All-purpose Potting Soil
First up is the all-purpose mix. As the name indicates, an all-purpose soil is a general mix of both organic and inorganic components. This type of bagged soil can be used for a variety of plants.
Organic components will include materials such as peat moss or bark. Whereas inorganic will refer to components such as perlite or vermiculite. There’s usually a bit of fertilizer mixed in there as well. The amount and type are dependent on the brand.
A good general purpose potting mix will be formulated to create fertile soil that allows for some water retention, good drainage, and good aeration. It should have a light and fluffy feel.
It should also be free of weeds, diseases, and insects. You’ll even see some mixes these days that are designed to be less prone to bugs, such as fungus gnats.
If the bag is exceptionally heavy or dense or has a funky smell, it’s best to leave it and pick a different bag.
An all-purpose potting soil is a great option for any container, whether inside or outside. You can use it by itself, or you can use it as a base to mix with other additives specific to your planting needs.
Perlite & Vermiculite
Both perlite & vermiculite are used in potting mixes to provide air space, make the soil less dense and improve moisture retention.
However, although both are volcanic in origin and super-heated for expansion, perlite is formed from volcanic glass. On the other hand, vermiculite is formed from mica, a magnesium-aluminum-iron silicate.
They are both lightweight, inorganic, and won’t decay. And both can be added to container soils or gardens.
The best way to describe perlite is that it resembles little white balls of styrofoam. It’s porous, so it allows water to drain quickly. This can help prevent the soil from becoming too compact. In turn, this increases the availability of oxygen to the plant’s roots.
Because it helps drain water, it makes a good additive for plants that don’t like their roots wet or like to dry out between each watering, such as succulents. Additionally, perlite has no nutritional value, so you don’t have to worry it may throw off the soil’s nutrient ratios.
You’ll often see perlite added to commercial mixes. It’s especially good for seed starting mixes since it helps aerate the soil and allows for good root expansion. One of the best times to use perlite with seeds is when you move your seedlings to their own individual pots.
But don’t limit yourself to seedlings. Personally, I often throw a handful of perlite in whenever I’m potting a plant.
Vermiculite, on the other hand, is brown in color and is better at retaining moisture. In fact, vermiculite will absorb 3 – 4 times its size in water.
Although it offers less aeration, it does attract different plant nutrients such as potassium and magnesium.
Vermiculite works best with water-loving plants, and plants that like moister soil.
As with perlite, you’ll also find vermiculite in many seed starting mixes. It’s best to use vermiculite as an additive for seed trays, as the extra water retention will help to give those seeds a good start.
Succulent & Cactus Soils
Another bagged soil you’ll often see on gardening center shelves is succulent and cacti mixes.
Succulents and cacti have different soil needs than other plants. They’re native to arid environments, so drainage is key with their soil.
A succulent and cactus soil needs to support the plant physically, so it doesn’t topple over. In addition, it needs to provide nutrients and hold just enough water for the plant to absorb.
Excess water should be able to drain away quickly. This type of soil should be completely dry within a day and a half of watering.
Tip – if you need succulent soil but your gardening center is out, opt for African violet soil. They’re very similar in design.
Commercial soils usually contain little organic matter, such as peat moss or coconut coir. This is because the organic matter will retain water. To help with drainage, your succulent soil should be porous and richer in inorganic materials, such as perlite or pumice.
You’ll also find good succulent soils often contain varied particle sized ingredients to maximize airflow.
As the name suggests, succulent and cactus soils are suited for these plant families. Depending on the brand, some soils can be used for other plants that will benefit from a quick draining medium.
Seed Starter Soils
A seed starting mix has a texture that is finer and lighter than that of a regular potting mix. And although you’ll hear this mix referred to as a bagged soil, in actuality, a seed starter mix contains no true soil or dirt.
In general, it’s made from a blend of peat moss or coconut coir and perlite or vermiculite. This type of mix is formulated to create an environment that encourages seed germination. After all, you want those seeds to sprout, and their roots to be able to stretch without meeting resistance.
Not only that, seed starting soils are sterile, so if you have a concern about mold or fungi, or your soil is less than desirable, then a seed starting mix will definitely help.
Not everyone needs a seed starting mix, especially when it comes to your garden. Personally, when I had a garden, I never used seed starter soil in the garden. However, I had good, rich soil. Also, I was never in a hurry to start early, so I didn’t start my seeds inside.
That said, for the new gardener, a seed starting mix is a good way to get a jump on your plants and to know that you’re giving your seeds the best chance of sprouting and becoming seedlings.
Garden soil is a mix of dirt and organic matter, such as compost, nutrients, and minerals, designed to be mixed in with your garden’s existing soil. Part of its purpose is to provide a good foundation for your plants and to help address any deficiencies your native soil might have.
Garden soil is intended for in-ground use only. This type of soil holds water longer, is heavier, and can become too compacted in a container. This can limit air space for root growth with your container gardening.
You can use garden soil to enhance your existing soil in your flower and perennial beds, or you can use it for your vegetables. Garden soil can also be used when planting your trees or shrubs.
For planting trees and shrubs, dig your hole and save the dirt from the hole. Then, mix the saved dirt with your bagged soil to use as your backfill. This will give your trees and shrubs a nice, fertile medium to establish their roots in.
Compost consists of decomposed organic plant and animal materials and is one of the best ways to give your soil a boost. To gardeners, this bagged soil is considered gold.
When I lived on the farm, we had our own compost pile. This rich, black dirt was one of the reasons my vegetable gardens thrived.
Compost will improve your soil structure, provide nutrients for your plants and provide beneficial microbes for the soil. And as an added bonus, compost continues its composting process even after it’s been spread in your garden.
Leaves, twigs, kitchen scraps, and manure, can all be used as composting materials if you are wanting to start your own compost pile instead of buying it as a bagged product
Tip – composting takes time, anywhere from a month to a year, depending on the material. In other words, don’t expect that the banana peel you threw in today will be ready for the garden tomorrow!
Composts formed from manure will be higher in nitrogen, and commercial products are often mixed with sand. Manure based compost is best used with in-ground gardens, mixed in with the existing soil. A good ratio to follow is two parts soil to one part compost.
However, composts made from other materials can be used in containers, in smaller amounts.
One thing to note, you want to add compost each year. However, be careful not to add too much year after year, as it may throw the nutrient ratios of your soil off.
Although many people use topsoil and garden soil interchangeably, they are actually two different mediums. Topsoil comes from the top 12” of the section of the ground being utilized. It’s screened to remove rocks and larger debris, and shredded to produce a fine, loose consistency.
There are different grades of topsoil, depending on where it was harvested. For example, topsoil taken from ground that is rich and loamy is going to have more nutrients than soil taken from an area that is mainly clay or has been depleted of its natural minerals.
When buying topsoil, it’s best to read the contents of the bag.
Lower grade topsoils are great for filling in patches or leveling holes. Whereas higher grade topsoils can be mixed in with your native soil, composts, or garden soils.
In general, straight topsoil shouldn’t be used on its own for planting as it may not contain the nutrients needed to support your plants.
As the name indicates, lawn soil is used primarily for repairing your lawn. Use it to fi in holes or uneven areas, and top off bare spots. This top dressing will also gradually improve your lawn’s soil over time, breaking down and giving it the nutrients it needs to keep your lawn healthy.
Commercial products use a mixture of ingredients and additives to help with water retention, which will provide better germination of your grass seed. Lawn soils can also contain fertilizers to help your grass grow thicker and stronger.
If your aim is to have a lush, thick lawn, then lawn soil is something you should consider.
I wanted to touch on the term “organic”, as you’ll see different soils that label themselves as organic.
The term organic means that the substance was animal or vegetable in origin and that it doesn’t contain chemicals or pesticides.
However, when it comes to soils, there’s no regulation of their labeling. A soil labeled “organic” will technically only contain natural, carbon-based materials. But, it doesn’t guarantee the materials were sustainably sourced, or that they’re environmentally friendly.
If purchasing organic is of importance to you, then look for soil marked as having been evaluated by the Organic Materials Review Institute, or otherwise, OMRI listed.
I hope you found this brief guide on different soils and their applications helpful. As we go along, I’ll be going into more depth on various soils, their compositions, and their uses
Although there are numerous bagged soils available, this list hopefully gave you a brief rundown of the most common ones. The main takeaway here is to make sure the product is suited to you and your plant’s needs. Some plants are not super fussy about soils, but others may have difficulty flourishing in a poor or improper medium.
If you found this beginner’s guide on types of bagged soils and mixes helpful, feel free to share it.