So you want to grow some microgreens at home. Maybe you’re looking for a fun and edible science project, or maybe you’re looking to have a little victory garden for yourself to supplement your diet - either way, congratulations! Growing microgreens at home is easy, rewarding, and fun. Here’s a little guide to help you along the way, with some tips we think every home grower should know.

Small Scale vs. Large Scale Microgreens Production

Growing microgreens at home is different from growing them commercially. Apart from scale, the required equipment for microgreen production is what most clearly distinguishes a commercial producer from a hobbyist. Today, remodeled warehouses and rooftops produce microgreens in climate-controlled greenhouses, usually through hydroponics (soilless growing). Commercial production typically involves a pricey, custom built system with fluorescent lights, humidity controls, pH and nutrient meters, as well as complicated plumbing, heating, and cooling, etc.

At home, a shallow plastic container with adequate drainage, a soil alternative growth medium, and a nutrient mix is all you need. You can get plastic trays and nutrient mix at a local gardening supply store or online, or you can punch holes into a plastic container yourself. Your container doesn’t need to be very deep, because you will be harvesting your crops before their roots get too long and large. If you’re feeling fancy, you can get a temperature controlled heat mat to keep your seeds warm and support germination, although a radiator or the top of a refrigerator usually does the trick. A sunny spot on your windowsill is ideal, but if you’re low on light a supplemental lamp can help your plants out and prevent them from growing too “leggy”.

Equipment List

- Two Plastic Containers (one container with holes with a solid one underneath)
- Soil Alternative (read below for a few options!)
- Seeds
- A sunny, warm spot
- Water access
- Commercially Available Nutrient Mix (necessary if you want to grow past the seven day mark and grow some true leaves!)
- Supplemental lamp (optional)
- Heat mat (optional)

Why Go Soilless?

Growing hydroponically (without soil) has several advantages. Above all, soil alternatives are sterile and free of pests and diseases. Soil is organic and alive, and as with any living thing, you cannot fully control it. The first step of pest management for a large scale farm or a home garden is prevention. Growing from seed and hydroponically are good first steps! Additionally, it might be a good idea to distance your hydroponics set up from any other plants you might already be growing – better safe than sorry

Another advantage to growing hydroponically is that your plants will grow faster after the cress stage of a plant, when seedlings are seeking nutrients from their roots for the first time. This is because hydroponically, you are feeding nutrients directly to a plant’s roots through water instead of the roots having to seek them out in soil. In hydroponics, nutrients are in an ionic state that the roots are ready to uptake; in soil, nutrients need to be broken down by microbial life (bacteria, enzymes, fungi) in order to be accessible to the roots.

Now that we’ve convinced you to give home hydroponics a try, here are a few soil alternatives that we like. This is by no means an exhaustive list, but it gives you an idea of some of the options available.

Cocohusk – this has the most “soil like” texture and look – it also retains a lot of moisture, and won’t dry out as quickly. If you have less control over your environment, this might a good option! Perlite can also be added as needed, making it a versatile option for a variety of conditions.

Biostrate / Cress Plate – These are interchangeable, and good if you have very rigid control over your growing conditions

Rockwool - sort of like an inert cotton candy made of stone! Sounds crazy, but you have to feel it to believe it. Rockwool is often sold in little cubes, making it easy to space out your seeds – but it also requires more precision when planting. For more info on rockwool, check out our Rockwool FAQ!

Rapid Rooters – you can plant your micros in rapid rooters – it will look something like the picture below, which makes for a fun presentation!

Let’s Begin!

First thing’s first: you need to decide what microgreens you want to grow. There are a lot of different kinds of microgreens out there – have fun and experiment! Since microgreens grow quickly, you don’t have to commit too long to any one kind of crop.

Get inspired! We're going to talk about some of our favorite microgreens tomorrow.

A selection of different micros can be grown together, which provides an attractive array of tastes and colors. For example, micro amaranth, arugula and kohlrabi commonly appear together. But not every mix will work, as different varieties have varying growth rates. For this reason, mustard (fast) and beets (slow) would be a difficult mix to grow successfully. The mustard would quickly crowd out the beets and you’d be like, “I should have read that Farm.One blog post more carefully before I wasted 12 precious grams of seeds.” Told you.

Here’s what different varieties grown together in one tray can look like – by using stencils to plant your seeds, you can make cool patterns or spell things out! We made this for an event for our friends at the Institute of Culinary Education using micro amaranth and micro arugula.

As for your space, a sunny windowsill is best. Be mindful of other plants that might have pests!

Prepare Your Growing Medium and Pots

Put your growing medium of choice into your container (the one with holes) and soak it in plain water. You can soak in water + nutrient solution, but it’s not necessary. Clean, cool tap water is enough! Now you can plant your seeds.

Microgreens need lots of light and good air circulation. You can plant your seeds in relatively high density, since they won’t grow to be very large. However, if they’re not given adequate room, you will quickly realize your mistake after coming back to a smelly, bacteria ridden tray. Growers will often use a certain weight of seeds per square inch, rather than the traditional concept of spacing individual seeds. For example, we plant our micro basil at 0.177 grams per square inch. (Hopefully this mixture of imperial and metric units made you wince.) Within a standard 10” x 20” grower’s tray, you might be using hundreds or even thousands of seeds for some varieties. Talk about efficiency.

The conditions ideal for sprouting seeds are also conducive to the growth of bacteria and harmful microorganisms – sanitize and clean your equipment, make sure your growing container has good airflow. Use clean water, and get your seeds from a reputable source (Johnny’s has a great selection, and they have a whole section of Hydroponic Performers), and check your seeds for any visible pests and bugs before planting.

A note on microgreens – a white fuzz might appear on the stems of your microgreens within the first few days after they germinate. This is different to mold – it’s a little tricky to distinguish between the two, so pay close attention.

This is mold. The seeds have not yet sprouted, so it’s definitely mold. This batch is going to have to go :(

This is the normal, good kind of white fuzz – notice how it’s coming from the roots, and it’s longer and more spindly and it branches off.

Ready for a mold vs. normal white fuzz pop quiz? See if you can tell if the following is mold, or the good kind of white fuzz.

Drumroll please!

The answer is…it’s mold! This one’s a little tricky because the stalks of these micros look a little like the roots – but the roots are all the way down at the bottom, burrowed into the growth medium, and the white fuzz is higher above the roots, wrapped around the stalks. Look at how closely those micros are together – it’s no wonder they succumbed to mold.

Cover with Paper Towel, Plastic Dome, Spray, & Keep Warm

A paper towel will do the trick, but you can purchase a clear plastic dome to fit onto your growing container. You can mist your paper towel or dome lightly with water for higher humidity. Place your container somewhere warm, like on top of a radiator or a fridge, or if you splurged on one – a heat mat. Ideal temperatures for seed germination are around 75-80 degrees Fahrenheit (24-27 degrees Celsius). Some seeds prefer a distinct cold period – this is called cold seed stratification, and you can choose to do it if you know that is what your seeds prefer.

Remove Paper Towel/Plastic Dome

After your seeds have germinated and started to grow roots, remove the paper tower or dome, and let your plants breathe and get lots of light. Also, move them off of the radiator/top of fridge/heat mat. Typically seeds need higher humidity and higher temperatures to sprout, then cooler temperatures and slightly lower humidity when mature. Air flow helps prevent mold growth which will also flourish in hot, humid conditions. If your plants don’t have enough light, they will go searching for it by growing their stems long, leaving you with a leggy plant and a poor stem-to-leaf ratio. If you’re using a supplemental lamp, keep it close to the plants to avoid legginess.

Watering

Honestly, there is no one best way to grow and water micros (lots of room for trial and error if you haven’t already noticed), and your watering intervals will depend on the micro climate you’re growing in (the temperature, humidity, airflow in your space. Generally speaking, if your medium is dry to touch – water it! Soilless media tend to hold less water than soil, so expect the watering intervals to be more than once per day, but perhaps not – again, this all depends on the micro climate in which you are trying to grow in. Your watering needs will also depend on the growing medium you’ve chosen to grow in. For example, cress plates have a very clear visual indicator – they look very different when they’re dry vs wet.

Now is the time to add nutrients to your water. Read the instructions on your nutrient mix, and add them to your water accordingly.

Harvest

When your microgreens are at a size you’re happy with (refer back to day two for growth times and cues!), take a pair of shears or scissors, and you’re ready to harvest. You can sometimes turn your microgreens into a “cut and come again” crop, meaning that your microgreens re-grow their tops after being harvested – something to keep in mind! If you’re just using micros for your own cooking, you can cut as you need and the other, uncut micros will happily live for several days or longer.

After you’re done with your microgreens, take your growing medium, squeeze out all the water, and compost it.

Take one of our classes, which range anywhere from a three hour intro to a two-day intensive to learn more about indoor farming and hydroponics, or you can take one of our fun, prosecco tours!

Thank you to Dan Bernstein for co-authorship of this article!

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