The health of your microgreens is dependent on the environment that they grow up in. Luckily, growing microgreens is a simple process that is easy for all indoor gardening enthusiasts. By taking some time to select the best possible medium for your seeds and plants, you will set them up for success with minimal effort.
In this article, we will touch on the most popular and successful growing mediums currently available. Here is a quick list of the best growing mediums for microgreens:
- Miracle-Gro Seed Starting Potting Mix – Best All-Around Medium
- Envelor Coir Plant Cover Coconut Husk Planters – Cleanest Growing Mat
- Terrafibre Hemp Grow Mat – Highest Seed Germination
- Biostrate Hydroponic Growing Mats – Most Sustainable Growing Mat
- Spongease Coco Coir Brick – Best Soil Alternative
*If you’re in a hurry, I’d recommend the Terrafibre Hemp Grow Mat as the best one. It’s a thick, durable, and all-natural option that creates the best yields.
Intro to Microgreens
Microgreens are the seedlings of herbs, greens, or other vegetables. They are not a specific breed of plants, but rather a plant that has been grown over a short period of time and has passed its “sprouting” phase. Microgreens are packed full of healthy nutrients and enzymes since the plants are in a period of young rapid growth.
Many vegetables and herbs can be grown into microgreens. Some great starter plants include radishes, red cabbage, kale, red mustard, amaranth, basil, cilantro, fennel, rosemary, mint, sage, broccoli, lettuce, spinach, chives, and wheatgrass.
Microgreens are great for people who want to grow their own food in a small area. They are also perfect for those who do not want to wait a full growing season before harvest. These plants are ready to eat a soon as 1 – 3 weeks.
They’re also a great source of antioxidants such as vitamins A, B6, C, K, and E. They also contain carbohydrates, proteins, fiber, folate, iron, sodium, and calcium.
If you would like to learn more about the microgreen growing process, check out our guide on how to grow microgreens indoors here.
Intro to Growing Medium
Growing medium, also known as media, is essential for healthy seed starting. You can use seed starting soil as a medium, as well as several other organic materials, such as growing mats. Here are three benefits that growing medium provides your plant in its early stages:
- It gives the roots access to air, water, and nutrients
- It allows for optimal root growth
- It supports the plant by physically holding it up
Choosing a growing medium that is high quality, organic, and sterile will give your plants a good chance at a healthy life. You can sterilize soil or medium by baking it in an oven at 180 F for 30 minutes. This helps eliminate unwanted pests and bacteria.
Do not use outdoor ground soil when starting your seeds! This can invite in unwelcome microorganisms that may compromise the health of the plant.
Your medium will need a container to go into. We recommend this growing tray for starting your microgreens. It is the standard size, meaning many medium mats are sized to fit perfectly into it. It is also highly durable which is important for reuse for seasons or even years in a row.
Choosing the Best Growing Medium for Microgreens
There are many options when it comes to choosing a growing medium for your plants. Here is a short list of some of the most popular materials you can try.
- Soil: Soil is the most common choice for microgreen growing as well as seed-starting in general. It is nutrient-rich and good at holding moisture for your plants.
- Coir: This organic material is made out of coconut shell husks and fibers. This material holds water and oxygen well, is organic, and is a renewable material, making it environmentally friendly. Unfortunately, it does not have great drainage, so is often best mixed with another media.
- Burlap: is the most affordable choice when it comes to a microgreen medium. However, it is one of the trickiest materials to work with and may not produce ideal yields as a result of it’s difficulty.
- Rockwool: Rockwool is a sterile and porous non-degradable material that is made out of limestone and granite. It holds water very well, has great oxygen retention, and comes in a variety of sizes and shapes. Like any material, it has drawbacks as well. It is not pH neutral, creates dust particles, and can be nearly impossible to dispose of in an environmentally friendly way.
- Vermiculate: This substance has great moisture and nutrient retention capacity. However, it is possible that it may hold too much water, and is an expensive choice.
Using soil as the medium for your microgreens is a great choice and our first recommendation. It is usually the cheapest solution because you can use the soil over and over again for each batch.
This Miracle-Gro Mix is the perfect solution if you would like your starter to do all the work, and to avoid the use of fertilizers and liquid additives. All you need to do is water it. It is a very lightweight formula, which is important for oxygen reaching your seedling. Customers have reported that the nutrients in the soil will support plants all season long without anything additional added to it.
The natural coco coir grow mats are and made of half-inch thick woven 100% natural coconut coir fibers. They are lightweight and easy to cut down to the size of your tray. These growing pads are cleaner and more convenient than soil. They’re easy to harvest from and minimize the possibility of mold on your seedlings.
These coconut coir mats are also great at draining water away from your seedlings, making sure not to overwater them. The water then sits in the bottom of your tray, available for your seedling’s roots when needed.
People have successfully resued these mats, however, the manufacturer advises against it. This makes the Envelor Coir option more expensive than using soil.
This growing medium is made out of hemp fibers, making it a natural and sustainable choice for starting your microgreens. These mats are offered in 3 different sizes and 5 different quantities, making it easy to customize to your growing needs.
The mat is 100% biodegradable and compostable and is pH neutral, which means it will be safe to dispose of in any way you see fit. However, they are unfortunately not reusable.
These mats are highly resilient to pests and mold, making them perfect for an indoor setup that requires low maintenance. They are also simple to set up. Just place the mat in your tray, sprinkle the seeds on top, water, and you are done! This is the perfect gateway mat for a beginner.
These mats require more watering than soil. An efficient way to water your seeds is by placing the water under the mat, which will prevent evaporation and retain moisture.
These mats fit the standard 10” x 20” growing trays and come in a pack of ten making them one of the most affordable options on this list. They have a high water holding capacity which means your seedlings will be consistently moist.
They are biodegradable, but many users have reported that they take a very long time to break down or compost. It is made out of fibrous felt-like material, and is also good for hydroponic planting.
To use these mats, soak one briefly in ph-neutral water, then drain it, and place it in a tray. Then pour your seeds on top of the mat. These mats, like a couple mentioned above, are easy to use and a less messy alternative to soil.
The Spongease Coco Coir Brick is a great alternative to traditional potting soil. Each Brick makes approximately 2 gallons of potting mix when broken up and rehydrated. This product is extracted from coconut pith, which is a renewable resource and by-products of the coconut plant shell.
It is a light and fluffy material that allows for oxygen to circulate around the seedlings and its roots.The manufacturer has made sure to sift and remove long fibrous strands and other impurities to make sure that the potting soil is mixed consistently.
If you don’t want to use all of the products at once, you have two options. You can rehydrate the whole brick and place the leftover potting mix into a container to be saved for later. Another option is to saw through the brake and only rehydrate a portion of it, but since is this a crumbly product, that may be a messy option.
Because of the simplicity of the microgreen growing process, it’s likely that any of the above mediums will have a high success rate of growth. When deciding on the best medium for microgreens, your main considerations are cleanliness, affordability, and reusability. While soil will always be a great choice for your indoor garden project, the medium mats can make the process even easier, which is perfect for beginners or those who want to keep the process very clean.
Pick what feels intuitively best to you from this list and experiment. If it’s a perfect fit, great. If not, try another. It is well worth it to explore your options for a couple of months to find the perfect fit. You’ll be happy in the end when you’ve determined which growing medium works best for you!