The Best Soil for Microgreens - What to Look For (And What to Avoid)

Posted in Reviews on February 8, 2021

Growing microgreens is the fastest, most comprehensible way to get your bow on daily servings of vegetables and herbs, even for the laziest of vegetarians. They are perfect as a garnish on a fresh-baked bagel, delicious in salads, and satisfying as a light meal by themselves. They also make great plant food for your balcony's houseplants! But if you want to eat gorgeous and nutritious vegetables, you'll need to choose the best possible soil for microgreens.

Being an integral part of the nutritional value of the plants, and thus the quality of the microgreens, the soil is the most important variable that you can control as you start your journey into the world of microgreens.

But what is the best soil for microgreens? Let's take a look at what you should look for and the qualities that make the difference. As Amazon Associate, we earn from qualifying purchases.

Best Soil for Microgreens:

Best soil would vary depending on your needs. And soil type and composition will vary from the type of vegetables and herbs you want to grow, to your microgreen garden's climate and to its geographic location.

However, most microgreen farmers will agree that the composition consists of ~80% organic material containing fertile topsoil, compost, leaf mold, and garden soil, and ~20% perlite.

There are a lot of formulas out there for making soil mixes for microgreens. You can even buy pre-made mixes or buy buckets with different ingredients that you must then mix together yourself. And regardless of the soil mix that you end up with, it must meet the following criteria:

1. Balanced pH level to ensure optimum nutrient availability. Most seeds, including microgreens, germinate best when given warm, moist soil that ranges between 6.0 and 7.0 pH.

2. Will retain water but drain well to avoid water-logging, which can suppress microgreen growth. The better the drainage, the more oxygen will be around the roots that in turn will help aerobic microbe growth.

3. Provide an excellent medium for the microgreens and help them grow into strong and hardy plants.

It is usually agreed upon that the best results are achieved by starting from a mixture of fertile topsoil, compost, leaf mold, and garden soil. This is a great mix of things that, when combined, will ensure the best results in all categories.

Top 3 Recommended Potting Mixes for Microgreens:

Growing microgreens at home is easier than you might think. That is if you can find good quality potting soil mix. If you don't use the best potting mix for microgreens, your plants may suffer in their early growth stages. Using poor soil can result in a lack of nutrients and too much moisture, or something with too much sand and not enough organic matter. If your microgreens fail to thrive, it's likely due to the type of potting mix you choose. Enlisted are three promising potting mixes for microgreens:

1. Burpee Organic Premium Potting Mix, 8 Quart:

Beginning organic farmers who are new to planting microgreens and herbs might not have an easy time conducting the sowing, watering, and feeding needed to keep their produce alive, yet Burpee is well equipped to provide users with a growing mix that makes the entire process easy on them.

Burpee offers an organic growing mix that is premixed and packaged in both 2-Quart and 8-Quart bags. This makes it easier for gardeners to obtain an optimal mix of nutrients, moisture, and well-drained soil for their microgreens.

In addition to being made of good quality 95% organic compost, this top-rated potting mix also contains peat, which helps give the soil nutrients for the microgreens.

The additional peat supplies water and releases the nutrients when needed. Gardeners also note that this potting mix has a good pH level, so the potting mix isn't going to burn the roots of your microgreens.

2. Espoma AP4 4-Quart Organic Potting Mix:

When quality is concerned, many would instantly talk about how the price of the product decides its caliber or worth. This is not the case with Espoma AP4 Organic Potting Mix. Users feel that they have more than compensated themselves with this purchase. Espoma AP4 4-Quart is on the list of the top-selling products for a reason: it's quality and affordable price.

This 4-Quart mix is rated as one of the best mixes for microgreens because it is well matched to the needs of its users. It provides all the nutrients and minerals that a garden requires. Espoma AP4 eliminates the guesswork for gardeners because it comes with a good pH balance and has organic materials and peat to add the necessary fertility, which makes it perfect for microgreens. Further boosted with earthworm casting, this potting mix can make your tiniest gardens more plentiful.

3. Sun Gro Black Gold Potting Mix:

If you're familiar with the gardening industry, then you've probably heard of Sun Gro. The company is a symbol of trust and quality, and their Black Gold Potting Mix (8-Quart) is no exception.

Sun-Gro Black Gold Potting Mix is an affordable organic potting mix perfect for microgreens. It comes in 8-quart bags and is offered at a price that will relieve your wallet. The product is made from a mix of various organic materials that form a nutrient-rich substrate and allows better moisture management and aeration. It also has a balanced pH level and is excellent for promoting root growth and plant development.

The organic substrate is also suitable for germinating seeds with its ability to release nutrients in a controlled manner. It also helps with water retention as the mix holds water, allowing the plant to store water longer. This also comes as another plus as it keeps the plant from drowning when re-watering.

The Main Ingredients in Microgreen Soil Mix:

A growing media for microgreens must be formulated with appropriate nutrients, moisture, and air holding capacity while maintaining a neutral pH level in order for the microgreens to grow with good health and strong plant structure. Barring the use of synthetic fertilizers, the main bulk materials for soil mixes include the following:

Peat Moss:

This soil conditioner is a must in a good microgreen soil mix and is usually one of the most important ingredients. Peat moss is made from decomposed plants that are harvested or collected in swamps where they have been laid down for years.

Because of the nature of peat moss, its structure is tightly packed with the plant material that holds moisture, holds nutrients, and also helps to hold the air that promotes the growth of the microgreens. Just like soil, peat moss is acidic in nature and safe to use for the growth of microgreens.

Without worries, it will rot roots or slow down their growth in any way.

Learn more on why you should use peat moss as a growing medium here

Coconut Coir:

Coconut coir is a great medium that is most often used in soilless potting media and has many benefits for growing microgreens. It is an organic material that can hold the right amount of moisture and supports the growth of the microgreens.

This potting material is harvested from the fibrous waste from the coconut husks, and then it is shredded, refined, and sterilized to create the finished product. Rich in potassium and many other trace nutrients, coconut coir is also useful for promoting root growth.

Perlite:

Perlite is a white granular material that is light, porous, and also very durable. It comes from heated volcanic basalt, which is a very good water-holding material. Although it is not a good soil conditioner alone, perlite is a very good component of a good microgreen growing mix. It improves drainage of the potting mix and increases aeration and moisture retention at the same time.

Limestone:

Limestone, or calcined lime, has recently gained popularity as a growing media with its ability to provide good pH buffering. Add to this its humic acid content and its ability to release calcium when needed for microgreens, and we have a great addition to a potting mix. So, if you are growing microgreens in soil, you will want to add a little limestone.

Organic Fertilizer:

Another critical component to a good soil mix is an organic fertilizer, which is a middle ground between purely organic and purely inorganic fertilizers. Organic fertilizers consist of natural soil amendments, specific blends of mineral nutrients, and amino acids. Because they don't contain synthetic ingredients, organic fertilizers actually make a significant difference to the microbial environment in a potting mix.

Conclusion:

Although there is no one formula for the perfect potting mix for microgreens, the most important criterion is that the mix should hold moisture but drain well. If you are planting microgreens in soil, the pH level also must be rebalanced by using a soil additive to create a neutral solution. The potting mix should consist of at least 80% organic material based on the ratios above, and the remaining 20% can be made up of perlite (only up to 15-20%) and other additives like compost, limestone, and other organic fertilizers if you choose.

Adequate soil nutrients are an important element in the growth of any plant, and this is true in the case of microgreens as well. Regardless of the variety of mix you choose, keep an eye out for the above three factors. These will help you to choose a soil mix ideal for the growth of your microgreens.