Whether you are new to microgreen gardening or have been growing microgreens for several years, you want to know what you need to reap a healthy crop of microgreens.
One thing that can impact the size of your crop is the growing medium used for your microgreens.
If you are interested in learning about the top growing mediums for microgreens, this is the article for you. We will break down the top five choices, along with the advantages and disadvantages of each type of growing medium for microgreens.
Coconut Coir
Coconut coir is one of the most common choices for microgreen growing mediums. This soilless option is comprised of everything of the coconut located between the out shell and the coconut seed. In the past, the coir of coconut was considered a waste product, until gardeners discovered how beneficial it is in the garden.
Coconut coir is created by loosening the husk by soaking it in water. Once the husk is removed and the coir is exposed, the coir must be dried, which can take longer than a year. Once dried, the coconut coir is processed into ground coconut coir, croutons, chips, or thin sheets of coconut coir sheets.
The Advantages of Coconut Coir for Microgreen Gardens
Coconut coir offers a number of advantages that should be considered.
- Moisture Retention – Coconut coir can hold more than ten times its weight in water, which means when standard care is provided, your microgreens will never dry out.
- Environmentally Safe – Coconut coir is a repurposed waste product that comes from a renewable resource. Furthermore, coconut coir can be used more than once for microgreen gardening.
- Insect Neutral – Insects do not like coconut coir, which makes it a great choice for those who are interested in pest management.
- Fine Textured – The fine texture of coconut coir ensures your seeds have time to grow and your growing medium has proper aeration.
The Disadvantages of Coconut Coir for Microgreen Gardens
Although coconut coir offers new advantages, there are also a few disadvantages that should be considered.
- Rehydration Required – Coconut coir is shipped dry and compressed. In order to use coconut coir, you must rehydrate it. When growing microgreens, you will need to water the coir three times before planting your microgreen seeds.
- Supplementation Required – Coconut coir does not contain any nutrients. Although it may look like soil, it does not have the nutrients that are found in soil. When growing microgreens in coconut coir, you may need to add nutrients to your water when you are raising microgreens in coconut coir.
Hemp Mats
Woven hemp mats are constructed from hemp fiber. These soilless mats look like a thick piece of felt. Many people like using woven hemp maps because they reduce the frequency of watering.
The Advantages of Woven Hemp Mats for Microgreens
Hemp mats offer a host of benefits for microgreen gardeners, including:
- Moisture Retention – Hemp offers extreme moisture retention, which is perfect for microgreen gardeners. Hemp maps evenly absorb and retain water.
- Environmentally Friendly – Hemp mats are extremely environmentally friendly and can be composted once you harvest your microgreens. Unlike other microgreen growing mediums, hemp pads break down in about two weeks when they are wet.
- Easy to Cut to Size – Hemp mats can easily be cut to the size of your microgreen growing trays. A simple pair of scissors is all you need.
- Aeration – Hemp offers excellent aeration, which reduces the risk of mold and other diseases.
The Disadvantages of Hemp Pads for Microgreens
Hemp mats also have a few disadvantages that should be considered.
- Flimsy Material – Hemp mats are easy to rip, especially when they are wet. This can be especially troubling when you are trying to harvest your microgreens.
- Fertilizer Required – Hemp mats do not contain any nutrients, which means you may need to add liquid fertilizer to your water to ensure your microgreens are getting the nutrients they need to grow.
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Hemp Fiber Grow Mats (10) Hydroponic Grow Pads - Grow Microgreens, Wheatgrass Indoors - Fits Garden 10" X 20" Germination Tray - Environmentally Conscious, Biodegradable - Natural fiber growth medium. The fibers of the industrial hemp plant are currently a byproduct in the farming industry. Hemp fibers are an incredibly resilient fiber similar to composition to coco coir but with a neutral pH.
- Promote sustainable growing practices with 100% biodegradable and compostable. Hemp Grow break down and decompose faster than other grow mats made from jute, paper, or coco coir.
- Excellent water absorption properties. This means you are watering less and can maintain a more consistent watering cycle.
- Fibers are separated through a decortication process without the use of any chemicals, and a needle punching technique creates a light texture for roots to easily grow through.
- Hemp Mats are all natural and pH neutral. Hemp fibers are intertwined into a biodegradable backing to provide a strong but light environment for seeds to thrive. pH neutral means less additives to keep your seeds happy.
Hydroponic Growing Mats
Hydroponic means that microgreens are not grown in soil; instead, they are grown using nutrient solutions. This soilless option is often made of synthetic fiber; however, natural fibers like jute, hemp, wood, and coconut can be used to create hydroponic growing mats for microgreens.
The Advantages of Hydroponic Growing Mats for Microgreens
Hydroponic offers a number of benefits that should be considered when choosing a growing medium for microgreens. You can choose organic natural fiber growing mats or a synthetic growing mat for microgreens.
- Clean and Convenient – Hydroponic grow mats for microgreens are exceptionally clean and convenient to use. The hydroponic mats for microgreens can be cut to size.
- Sterile – Hydroponic pads for microgreens are sterile, which reduces the risk of mold and soil based diseases.
- Water Drainage – The fiber pads prevent overwatering thanks to their ability to drain quickly. This results in higher crops and a decreased risk of problems.
- Easy to Store – These grow pads are easy to tuck away in a drawer or closet when you don’t need them.
The Disadvantages of Hydroponic Grow Mats for Microgreens
Hydroponic growing pads for microgreens also have a few disadvantages that should be considered.
- Slow to Biodegrade – Although most grow mats are labeled as biodegradable, it can take months or even years for them to biodegrade naturally.
- Cost – Grow pads for microgreens are considered a single-use growing medium, which means you must reorder mats for each batch of microgreens.
Potting Soil
Potting soil is the most common growing medium used for microgreen seeds. When it comes to choosing soil, you want one that is organic.
The Advantages of Potting Soil
Potting soil has several advantages that a microgreen gardener should consider, including:
- No Nutrients Needed – Potting soil, especially organic potting soil, provides your microgreen seeds with the nutrients they need to grow strong.
- Sterile – Commercial potting soil is sterile and free from pests, which is especially important for indoor plants and microgreens that will be grown in your home. These pests can harm your seedling or even get into your home.
- Fine-Grained – Microgreen seeds need soil that is fine-grained. This type of soil allows roots to easily develop.
- Balanced – Potting soil has a balanced pH, which means that your microgreens will thrive when planted in potting soil.
The Disadvantages of Potting Soil
Potting soil has several disadvantages, including:
- Messy – Potting soil is messy, especially if you are using it indoors. It can easily be spilled out and scattered across your work surface and floor.
- Synthetic Ingredients – Some potting soils contain synthetic ingredients, which cannot be used in organic microgreen gardening.
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Vermiculite
Vermiculite is a mineral that has a neutral pH and can be used for growing microgreens. The natural sterile and mold-resistant growing medium increases microgreen yield.
The Advantages of Vermiculite
Vermiculite offers several benefits that should be considered when choosing a growing medium.
- Aeration – Vermiculite is lightweight increases the amount of aeration that your microgreen roots receive, which can reduce the risk of mold and other diseases.
- Retains Water – It takes a long time for each vermiculite particle to dry out, which means vermiculate will hold water and nutrients for an extended period of time.
- Fertilizer – Vermiculite is a mineral that contains trace minerals, including potassium and magnesium that plants need to grow.
- Affordable – Vermiculite one of the most affordable growing mediums on the market. Furthermore, you can reuse it over and over since it does not decompose.
The Disadvantages of Vermiculite
- Not Environmentally Friendly – Vermiculite is a nonrenewable resource. It does not break down and cannot be added to the compost pile.
- Raises pH Levels – The carbonate compounds found in vermiculite can raise the pH level of your growing medium.
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Final Thoughts
Each growing medium has advantages and disadvantages. Choosing a growing medium ultimately comes down to personal choice; however, there are certain things you should do to ensure a large harvest.
Your growing medium must properly drain. If too much water remains in the soil, it can increase the risk of fungi growth. Make sure your microgreens do not stand in water. Water from the bottom, allow the water to soak into the soil for 30 minutes and then remove any standing water from your growing trays.
Ensure you are using the proper seed density. Different types of microgreens require different seed densities. When seeds are planted too closely together, it increases the risk of fungal and mold problems. Plant seeds as directed to improve water drainage and improve your crops.
Use the proper equipment, including growing trays, organic seeds, grow lights, and circulation fans. When the proper equipment is used, your odds of a successful crop increase dramatically. The right tools will also reduce the amount of time you need to spend gardening your microgreens.
