Develop Onion Microgreens Shortly and Simply

From winter to bundling to green, there are tons of cool onion varieties. They may come in different colors and flavors, but they all have one thing in common: onions are great microgreens! Onion microgreen is easy to care for, delicious, and the perfect new garden project.

If you haven't tried growing microgreens before, it's definitely worth trying. Like a sprout, a microgreen is a young plant that is harvested early because of its delicate taste and excess nutrients. In contrast to sprouts, however, microgreens are grown until they develop their first leaves (cotyledons), which optimizes the culinary properties.

Onion microgreens are one of the more unique options. These long, thin greens hang from their black seed coats, which gives them a dotted look. The peels are edible and are said to have a garlic flavor. The onion microgreens themselves are hearty and have a stronger onion flavor than you think. They taste delicious when cooked like chives or chopped green onions.

Onion microgreens are very easy to grow, but they grow slowly (you may want a faster plant if this is your first time growing microgreens). It will take between 12 and 21 days for these fresh greens to be ready to harvest. Once the time comes these onions will definitely be worth it!

Good products on Amazon for growing onion microgreens:

Onion microgreens short info

Tokyo Long White Bunching Onion Microgreens.

Taste: Hearty onion flavor; Garlic aftertaste
Soaking: Optional
Rinse / Drain: No
Germination: 3 to 4 days
Ideal harvest: 12 days

Growing onion microgreens

Onion microgreens require the same materials as any microgreen to grow. Most of these can be reused so you can experiment with other types of microgreens later.


  • Seeds: any kind of onion seeds (we especially like the quality seeds from True Leaf Market)
  • Containers: At least two flat containers that can be punched with holes like this one
  • Growing medium: Espoma seed starter mix or coconut coconut
  • Light: We had success with the Agrobrite T5 Grow Light, but you can definitely check out our other favorites
  • spray bottle
  • Kitchen scissors

And since we already mentioned the True Leaf Market onion seed, let's share some of our favorites:

Utah Yellow Sweet Spanish onion seeds

You may be wondering: Don't onions grow from onions, don't grow from seeds? It turns out these plants can do both, but seeds are most efficient for onion microgreens – mostly because we want to grow them close together. Because the seeds are so small and planted tightly in the ground, you may want to buy them in bulk. You will need at least half an ounce of seeds per 10 × 20 inch bottom tray.

Although seeds are the norm, you can plant bulbs sets for larger bulbs instead. Note that onions do not produce grass-thin microgreens like seeds do. If this is what you want to try, we recommend checking out our article on planting onions.

Seed starting soil is usually the best for growing microgreens. However, onion microgreens also grow well in coconut coconut. This medium stores moisture better than the soil, so you don't have to water as often.


Onion seeds are tiny and don't need to be soaked before planting. However, a few hours in water can help them germinate faster. So it's up to you.


We want to grow onion microgreens like a dense mat of grass. This saves space and optimizes our harvest. To start, punch some water drainage holes in a growing bowl and fill them with soil almost to the brim. Pack up the soil and use the spray bottle to moisten it. We are now ready to plant seeds!

Spread your Microgreen seeds all over the soil surface, including the corners of the tray (you may want to use a shaker bottle). The seeds should be close together. However, you need to make sure that they are not touching. If they grow too tight, onion seeds will make the perfect habitat for fungal growth in the soil. Instead of covering them with soil, release the seeds.

After planting your onion seeds, give your onion seeds a good splash of water to germinate, then place the second tray directly on top (right side up). This leads to a blackout, in which the onion seeds germinate and are simultaneously pushed into the soil. You can even add up to 5 pounds of weight to the cover to ensure that light does not get into the seeds. As the onion microgreens begin to grow after germination, they will work together to push the cover and weight up.


Crystal White Wax onion microgreen

Keep your planted seeds in the dark for at least 3-4 days. They probably don't need watering during this time. When the seeds grow into seedlings and are yellow in color, you can remove the seed coat. The rungs seem compressed at first, but they quickly stand up (and turn green) in the light.

Place your onion microgreens right under the grow light. We prefer artificial light for microgreen growing indoors as the shoots grow towards the light. If the trays are simply placed on a windowsill, the microgreens will grow unevenly. With a grow light, you can also control exactly how much light the trays receive each day (we recommend 8-12 hours).

Do you remember how we try to prevent fungus from growing? Perhaps the most important precaution we can take is bottom watering the tray. This will keep the microgreens dry and less inviting for fungus to spread.

To water from below, take your second tray. Fill it with a couple of inches of water and put the growing tray inside. Let the soil drink the water for about 10 minutes and then remove it. Repeat this watering process when the soil begins to dry out.


Onion microgreen has a larger window than most for harvesting. You can harvest piece by piece instead of all at once (although you can certainly only get one big harvest). Note, however, that the micro-green taste changes as it ripens, so you don't want to wait too long. Sometimes the onion microgreens also dry out at the tips as they continue to grow.

Start harvesting your onion microgreens when they are 4 inches tall and lean forward (they look like uncut grass). Use clean kitchen scissors (or similar) to secure the onion microgreens in bundles that are at least 1 cm above the surface of the soil.

Onions grow from the bottom of the stem instead of the top. This means that we can press a second crop out of the skins. Simply care for the microgreens until they grow back and can be harvested again.


After harvesting, wait to wash the onion microgreens until you are ready to use them. As mentioned earlier, you can keep the seed coats or remove them from the bulbs. No matter what you choose, each delicious green has a great, hassle-free onion flavor (they won't even make you cry if you chop them!).

Store your microgreens, onions, or any other in a sealed container in the refrigerator. They should stay fresh for up to a week – especially if you put a paper towel in the bag to soak up extra water.

frequently asked Questions

Red Burgundy Onion Microgreens

Q: What are onion sprouts good for?

A: Both onion microgreens and sprouts are packed with nutrients. They can be added to green salads, sandwiches, casseroles, stir-fries, and anything else that benefits from the flavor of the onions.

Q: Which is healthier, sprouts or microgreens?

A: We have to choose microgreens. They're significantly larger than sprouts, so you get more nutrients, health benefits, and flavor (especially with onions!).

Q: Can microgreens make you sick?

A: As long as you follow the instructions carefully, your microgreens should be safe to eat. Home grown food disease is usually due to pesticide spray or diseased plants.

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