How To Grow Microgreens (With and Without Soil)

Microgreens are no longer reserved for fancy or high-end restaurants since they’ve gained mainstream popularity. Due to their rich flavor and numerous health benefits, these tiny veggies and herbs are highly-priced at most grocery stores. However, you can save money and grow your own microgreens at home!

Here’s how to grow microgreens – with and without soil:

  1. Gather the required materials.
  2. Prepare the growing medium in the trays.
  3. Plant the seeds.
  4. Germinate the seeds.
  5. Uncover the growing trays.
  6. Harvest the microgreens.

This article will explore how to grow microgreens with or without soil. But, before we get into the process of growing microgreens, let’s find out what microgreens are and why they’ve become popular.

All About Microgreens

Microgreens are young vegetables, greens, or herbs that grow to approximately 1 to 3 inches (2.5–7.5 cm) tall. They are also known as vegetable confetti or micro herbs. 

Microgreens are usually harvested after the seeds have germinated and the cotyledon leaves have appeared. So, you can grow and harvest them 7 to 21 days after germination.

They’re Different From Sprouts and Baby Greens

Many people confuse microgreens with sprouts and baby greens. So, how do you differentiate the three?

Sprouts comprise underdeveloped leaves that form immediately after germination (after a day or two). They’re the first stage of a seed’s development, and they aren’t grown in a growing medium.

On the other hand, microgreens are the second stage of a plant’s development. They’re harvested at the peak of flavor intensity (after 7-21 days). They have the plant’s first true (cotyledon) leaves and established roots. 

Contrastingly, baby greens form when the plant grows beyond the microgreens stage. Though harvested in a juvenile stage, they have adult leaves, and their flavors resemble those of mature plants.

They Provide Flavor and Nutrients

Microgreens have been used as garnishes in restaurants for decades since their advent in the 1980s. Their rich flavor and nutritious punch make them an ideal addition to stews, soups, and various dishes.

The seeds of various vegetables and herbs are ideal for growing microgreens, including the following:

  • Cabbage
  • Broccoli
  • Lettuce
  • Carrots
  • Celery
  • Amaranth
  • Swiss chard
  • Melon
  • Squash
  • Cucumber

As I mentioned earlier, microgreens are not only flavorful but very nutritious. These tiny plant varieties are packed with numerous nutrients.

Some of these nutrients include the following:

  • Iron
  • Zinc
  • Potassium
  • Copper
  • Magnesium

Clearly, microgreens are great sources of beneficial plant antioxidants and vitamins.

Closeup of broccoli microgreens

They Are Shown to Limit Chronic Diseases

Studies show that microgreens have high concentrations of nutrients and antioxidants. Polyphenols are the most abundant types of antioxidants in microgreens.

They are linked to minimizing the risk of chronic diseases, including:

Heart Disease

An animal study revealed that polyphenols reduce triglyceride and bad cholesterol levels in the body. Therefore, these antioxidants prevent chronic inflammation, reducing the risk of heart disease.

Diabetes

Diabetes develops when there’s a significantly high glucose concentration in the blood. Antioxidants in plants minimize the stress that inhibits the uptake of sugars by the cells, limiting their concentration in the bloodstream. According to research findings, fenugreek microgreens enhanced glucose uptake by 25-44%.

Alzheimer’s Disease

Polyphenols in plants, including microgreens, reduce free radicals that cause chronic disorders such as Alzheimer’s disease (AD). AD is a form of dementia characterized by reduced cognitive function, especially in old age. Polyphenols minimize the risk of this disorder by minimizing any alterations that could cause cognitive deficits.

Cancers

Most cancers develop from poor diets and lifestyles. Polyphenols have been shown to have the potential to prevent and treat some cancers. This is due to their antioxidant and anti-inflammation properties. Different polyphenol classes, including flavonoids, lignans, phenolic acids, and stilbenes, have anticancer efficacies.

Now, with some background on microgreens and their benefits, let’s dive into the procedure of growing microgreens at home.

1. Gather the Required Materials

The two main methods of growing microgreens are using soil or a soilless medium. Your method of choice will depend on some factors, including your preferences and the availability of materials.

However, despite the approach, microgreens should have all the requirements necessary for growth, such as water, nutrients, and light.

Here’s what you’ll require when growing microgreens:

  • Microgreen seeds
  • Growing medium
  • Nutrients
  • Water
  • Growing trays
  • pH testing kits
  • Grow lights
  • Spray bottles

With these materials and the proper amount of care and attention, you’ll have your own microgreens growing in no time.

Purchasing Seeds Online or in Nurseries

The best way to produce microgreens is by planting seeds of vegetables or herbs. You can find microgreen seeds in your local nursery or seeds store and on online platforms like Amazon and eBay. But, be keen since you should only purchase chemical-free seeds specific for growing microgreens.

Microgreen seeds vary in size, depending on the type of plant. So, some are large-sized while others are tiny. Also, you can sow some seeds outdoors, but most are fragile and have higher survival rates when planted indoors.

For beginners, it is advisable to plant one type of seed variety per growing tray. However, if you’re accustomed to growing microgreens, you can have a combination of seeds in one container. 

Alternatively, you can buy a pre-selected packet of different microgreen seeds (for salad mixes). They contain various seed types with matching growth rates, beautiful color combinations, compatible flavors, and similar requirements.

Suitable Growing Medium

Microgreen seeds can grow in different media if they receive the necessary growth requirements. A medium is an essential component, as it provides anchorage for plant roots and is the nutrient reserve. Soil and hydroponics are the most preferred options for growing microgreens.

The soil-based method mainly involves soil and water only, though you can add nutrients. On the other hand, the soilless approach entails using inert growing media and nutrient-rich water.

Various types of media are suitable for growing microgreens, including:

Potting Mix

Potting mix is a soilless medium comprising all the vital conditions for plant growth. Most potting mixes are organic, containing microorganisms to aid plant growth. A potting mix can be made from different materials, including peat moss, perlite, and vermiculite.

Vermiculite

Vermiculite is an affordable, sterile, and lightweight medium made from a natural mineral. Vermiculite has a high water-retention capacity, which is preferable when you don’t want to water your plants. However, too much water causes root rot, so vermiculite is sometimes mixed with perlite to prevent waterlogging.

Coconut Coir

Coconut coir is one of the cheapest growing media. But, it requires prior preparation, which involves soaking the coir in water for about an hour.

Hemp Mats

Hemp mats are one of the best growing media due to their effectiveness. Hemp mats are less messy and easy to use. However, they’re for one-time use only and more costly than other types of media.

Rock Wool

Rock wool is an artificial mineral fiber made from melted and spun rock. Rock wool fibers form compact cubes that break apart to allow seeds to grow. Therefore, it is widely used in soilless farming, as it retains water, enables aeration, and is less messy. The only downside of rock wool is that it isn’t biodegradable.

Clay Pebbles

Clay pebbles comprise heated and expanded clay that forms porous pebbles. They’re also one of the most sought-after growing media in hydroponics because they have high water and air retention. They’re also washable and reusable.

A Rich Nutrient Source

All plants require essential minerals to grow and thrive. Every microgreen seed variety needs a specific concentration of nutrients. Although the seeds provide some nutrients, it’s advisable to add some to ensure that you’ve met their nutritional needs.

Apart from supporting the roots and enabling aeration, a growing medium should be nutrient-retaining to provide vital nutrients to the growing microgreens. If you’re using soil from your backyard as a medium, ensure it is fertile to support plant growth. Alternatively, you can buy potting soil containing compost, minerals, and organic matter.

Avoid Standard Potting Soil

Potting soil is not the best medium for growing microgreens because it is heavy, compact, and unsterile (may contain pathogens and weed seeds). These conditions can make it difficult for microgreens to grow. Instead of using potting soil, consider using a potting mix. 

Potting Mix Provides Vital Nutrients

You can buy or prepare a potting mix (for the soilless approach) that contains all the required nutrients. A potting mix is ideal for growing microgreens since it is sterile, lightweight, and fluffy. Most potting mixes are organic and contain components to facilitate aeration and water drainage.

Enrich Water Used for Hydroponic Growth

If you’re growing microgreens hydroponically, it is advisable to enrich the water with essential nutrients for optimum uptake by the plant roots. So, in this case, you only have to add liquid fertilizer (preferably organic) to the water to form a nutrient-rich solution.

Good-Quality Water

Water is a vital component when growing microgreens, regardless of your method. It generally helps in plant growth by facilitating metabolic processes in the cells. Water also helps in the uptake of essential nutrients by the roots.

In the soil-based approach, water is simply added to the growing trays to keep the soil moist and facilitate plant growth. However, water is the nutrient reservoir in the soilless method (especially methods involving hydroponics). While using such methods, the growing trays are suspended in nutrient-rich water continuously.

Test Water Quality Before Planting Microgreens

Before planting the microgreen seeds, you must ensure that the water quality is good. It should have the optimum pH for plant growth (5.5–6.5) and be chemical-free. Rainwater is the most suitable type of water to use when growing microgreens because of its natural acidity and dissolved oxygen levels.

Testing and preparing water is usually the first step when growing microgreens hydroponically. It involves testing the water quality for pH and other parameters.

If the pH is way above the optimum, add phosphoric acid to lower it. In contrast, if it is too low, you can add wood ash or lime to raise it.

If you’re using tap water, allow it to stand overnight to remove any chlorine in it. Alternatively, you can filter or boil it and let it cool to quickly remove unwanted chemicals and contaminants more quickly.

Distilled water is a good alternative as it is void of contaminants and minerals. However, it has a neutral pH of 7.0, requiring additional steps to acidify it enough for your microgreens to thrive.

Plastic Growing Trays

Growing trays are containers used for growing microgreens. You can use any type of tray at home for this purpose as long as it is 1.5–2 inches (3.8-5 cm) deep and not less than 20 inches (50 cm) long. But, it is preferable to buy the standard 10 by 20-inch (25 by 50 cm) plastic trays for microgreen use.

When growing microgreen seeds hydroponically, you can use plastic growing trays with no holes to hold hydroponic growing pads. You’ll fill the tray with nutrient-rich water, soaking the pad where you’ll spread the seeds. If a growing pad is unavailable, you can use a paper towel instead.

pH Testing Kits to Monitor Water Quality

When growing microgreens hydroponically, it is crucial to maintain the appropriate water quality. For instance, if the water’s pH is higher or lower than the optimum level, your microgreens will not flourish. pH testing kits come in handy when testing the water to determine whether it is ideal for planting your microgreen seeds.

Grow Lights to Aid in Photosynthesis

Natural light (sunlight) is sufficient for growing microgreens outdoors. But, if you’re planning to grow them indoors, you’ll need supplemental lighting.

You don’t need light for the first 4-5 days because the seeds are germinating. The plants will require light after developing leaves for photosynthesis.

Growing lights are essential when producing microgreens hydroponically. Be sure to invest in high-quality growing lights that imitate natural light by providing a full spectrum of absorbable light.

Spray Bottles to Effectively Water Small-Scale Plants

Spray bottles are the most effective tools for watering microgreens. Still, it’s not advisable to use a used spray bottle, especially if it previously contained chemicals. The best option is to buy a new spray bottle for regular misting of your microgreens.

2. Prepare the Growing Medium in the Trays

After ensuring that the water quality is ideal for planting, the next step is to prepare the growing medium. The soilless method involves placing the medium in the growing tray and soaking it in water. For this method, make sure that the medium is wet but not soggy.

If you’re using the soil-based method, here is the procedure:

  • Put about 1.5-2 inches (3.8-5 cm) of soil in the growing trays and spread it.
  • Tamp it gently to create a flatbed but make sure it is not compact.
  • Sprinkle the tested water to dampen the soil without flooding it.

3. Plant the Seeds

Planting microgreen seeds is easy. If your seeds are tiny, you only have to spread them evenly across the tray. However, large-sized seeds require pre-soaking before planting. This process breaks seed dormancy. After soaking the seeds, rinse them using flowing water to get oxygen.

After spreading the seeds, you don’t have to cover them with soil. You just have to keep them moist by spraying water occasionally using a spray bottle.

4. Germinate the Seeds

After sowing, microgreen seeds require a dark and warm environment to germinate. Cover the growing tray and ensure that the room’s temperature is around 70 °F (21 °C). However, the seeds still need water; so spray the growing trays every 12 hours.

It’s advisable to use the purified and tested water that you initially prepared to ensure that there are no pH fluctuations. About 15-20 evenly distributed spraying intervals will be ideal during germination. After each spray, re-cover the growing tray.

The germination process for most seed varieties is 4-5 days. After the fifth day, you should start noticing some sprouts. However, some microgreen seeds, including beets and cilantro, can take up to 7 days to germinate.

5. Uncover the Growing Trays

Once germination has taken place, you need to uncover the growing trays and expose them to sunlight. Exposure to light will facilitate photosynthesis. You can simply place the trays near a window to access direct sunlight or use the growing lights.

At this point, the microgreens don’t require a lot of moisture. So, you should only water them when necessary. If you’re using two types of trays (with and without holes), utilize the dry and soak watering method.

The Dry and Soak Method Prevents Excess Watering

The dry and soak method involves only adding some water to the bottom tray and removing the excess water after 10-20 minutes. Avoid using a spray bottle to water the seeds since there shouldn’t be any contact between the leaves and water.

It’s also advisable to leave the windows open to facilitate air circulation and prevent moisture build-up.

Monitor the Plants Carefully

In the next couple of days, monitor the microgreens daily, ensuring that they have enough water and light. The light could be insufficient if you notice that the shoots are leaning toward the window.

If you’d placed them on the north side of your house, transfer them to the north side for optimal growth and accumulation of antioxidants.

6. Harvest the Microgreens

Your microgreens should be ready for harvesting in about 14 days after germination. The maturity duration will depend on the seed variety. Most people harvest them between 10-14 days, while others wait until the 21st day.

It’s best to harvest microgreens once you notice the first set of true leaves, as this is the stage when the crops are at the peak of their flavor and nutrient intensity. The exact time you harvest will depend on your preferences.

Harvesting by Uprooting or Cutting

You can harvest the whole crop by uprooting it since all the parts are edible. Alternatively, you can cut the shoots using a knife or scissors if you don’t need the roots. Then, wash the microgreens before consumption.

It is preferable to eat the microgreens the same day you harvest them because they have a short shelf life. But, if you want to keep them for a couple of days, place them in an airtight bag and store them at a low temperature.

Conclusion

Microgreens are tiny versions of vegetables and herbs. They’ve gained popularity due to their rich flavors and nutritional benefits. Moreover, microgreens are easy and quick to grow, as they don’t require much space or a lot of water. With the right materials—and a little bit of time—you can grow your own microgreens at home.

Alexander Picot

Alexander Picot is the founder of TheGrowingLeaf.com and its lead content writer. He created the website in 2022 as a resource for horticulture lovers and beginners alike, compiling all the gardening tips he discovered over the years. Alex has a passion for caring for plants, turning backyards into feel-good places, and sharing his knowledge with the rest of the world.

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