Microgreens are one of the most rewarding things you can grow indoors. They require almost no space, they are ready to harvest in seven to fourteen days, and they pack a nutritional punch that rivals or exceeds their fully grown counterparts. Whether you have a sunny windowsill, a grow-light shelf, or just a corner of your kitchen counter, you can produce a steady supply of fresh, flavourful greens for a fraction of what they cost at the grocery store.
This guide walks you through everything: choosing your trays and growing medium, picking the right seeds, managing light and water, timing your harvest, and understanding the real cost savings. If you have never grown anything before, microgreens are the perfect starting point. If you are an experienced gardener, they fill the gap between outdoor growing seasons beautifully.
What Are Microgreens and Why Grow Them
Microgreens are young seedlings of vegetables, herbs, and other plants harvested after the first true leaves appear — typically seven to fourteen days after sowing. They are not sprouts, which are germinated seeds eaten root and all within a few days. Microgreens grow in soil or a growing medium, develop stems and leaves, and are cut just above the soil line at harvest.
The nutritional density of microgreens is remarkable. Research from the University of Maryland found that many microgreen varieties contain four to forty times higher concentrations of vitamins and carotenoids compared to their mature counterparts. Red cabbage microgreens, for example, have roughly six times more vitamin C than mature red cabbage. Broccoli microgreens are rich in sulforaphane, a compound linked to anti-inflammatory benefits.
Beyond nutrition, the practical appeal is straightforward. Microgreens grow fast, they grow indoors year-round, they need minimal equipment, and they taste excellent. A single ten-by-twenty-inch tray can produce enough greens for salads, sandwiches, and garnishes for a week or more.
Tray Setup and Equipment
The basic setup for growing microgreens is simple: a shallow tray with drainage, a growing medium, seeds, a cover for the blackout phase, and a light source. You do not need expensive hydroponic systems or specialised equipment to get started.
Standard ten-by-twenty-inch nursery trays are the most common choice. You need two trays per growing station: one with drainage holes for planting, and one solid tray underneath to catch water. The planting tray should be about one to two inches deep — microgreens have short root systems and do not need much depth.
For the blackout phase, you will need a third tray or a piece of cardboard that fits over the top. During the first few days after sowing, seeds germinate in darkness, which encourages them to stretch upward and develop strong stems. Some growers place a small weight on top of the cover to create gentle pressure that strengthens the stems further.
A spray bottle is essential for the early days when seeds are germinating and delicate. Once the greens are established, bottom watering — pouring water into the solid tray underneath — is more effective and reduces the risk of mould. You will also want a sharp pair of scissors or a clean knife for harvesting.
Choosing Your Growing Medium
Three growing mediums dominate the microgreen world: coconut coir, potting soil, and hemp mats. Each has advantages, and your choice depends on your priorities.
Coconut coir is the most popular option among dedicated microgreen growers. It is lightweight, sterile, retains moisture well, and is easy to work with. You can buy it in compressed bricks that expand when soaked — one brick typically fills several trays. Coir is also compostable, so cleanup is simple. A brick that costs three to five dollars will last through ten or more trays.
Potting soil works perfectly well, especially if you already have some on hand. Use a fine, seed-starting mix rather than chunky garden soil. The main drawback is that soil can harbour mould spores, so good airflow is more important when using soil as your medium. On the positive side, soil provides trace minerals that can enhance flavour and nutrition slightly.
Hemp mats are pre-cut fibre mats that fit standard trays. They are clean, consistent, and virtually eliminate mess. You simply lay the mat in the tray, wet it thoroughly, and sow your seeds on top. The downside is cost — hemp mats run about one to two dollars each, which adds up if you are growing continuously. They also hold less moisture than coir, so you may need to water more frequently.
For beginners, coconut coir is the best balance of cost, performance, and ease of use. Spread it about one inch deep in your tray, moisten it until it is damp but not waterlogged, and you are ready to sow.
Seed Selection: The Best Varieties to Start With
Not all seeds are created equal when it comes to microgreens. Some varieties germinate quickly, grow vigorously, and taste great with minimal fuss. Others are slower, fussier, or less flavourful. Start with the reliable performers and expand from there.
Sunflower microgreens are the crowd favourite for good reason. They produce thick, crunchy stems with large cotyledon leaves and a nutty, slightly sweet flavour. Soak the seeds for eight to twelve hours before sowing to speed germination. Harvest in ten to fourteen days. Use black oil sunflower seeds, which are inexpensive and widely available.
Pea shoots are another excellent beginner choice. They taste like fresh peas — sweet and bright — and grow tall enough to give you a generous harvest. Soak for eight to twelve hours. Harvest in ten to fourteen days when tendrils start to appear. Regular field peas or snow pea seeds both work well.
Radish microgreens are the fastest growers in the microgreen world. They germinate within a day or two and are ready to harvest in as little as five to seven days. The flavour is peppery and spicy, making them an excellent garnish for soups, tacos, and grain bowls. No soaking needed.
Broccoli microgreens are prized for their mild flavour and high sulforaphane content. They germinate in two to three days and are ready in eight to twelve days. The seeds are tiny, so sow them densely and evenly. No soaking required.
Other reliable varieties include wheatgrass, kale, cabbage, mustard, and amaranth. As a general rule, brassica family seeds (broccoli, kale, cabbage, radish, mustard) are among the easiest and fastest microgreens to grow. Avoid very slow germinators like carrots and celery until you have some experience.
Purchase seeds labelled specifically for sprouting or microgreen use. These are typically untreated and tested for germination rates. Buying in bulk — one-pound bags rather than small seed packets — drops the cost dramatically. A pound of radish seeds can produce dozens of trays.
Sowing, Blackout, and Light
The growing process follows a simple rhythm: sow, blackout, expose to light, water, harvest.
Spread your moistened growing medium in the tray to about one inch depth. Scatter seeds densely and evenly across the surface. For microgreens, you sow much more thickly than you would in a garden — the goal is a dense carpet of greens. As a rough guide, use about one ounce of small seeds like broccoli per ten-by-twenty tray, or two to three ounces of larger seeds like sunflower or pea.
Mist the seeds lightly with a spray bottle, then cover the tray with your blackout lid. Place a light weight on top if you want stronger stems. Set the covered tray in a room-temperature location — 18 to 24 degrees Celsius or 65 to 75 degrees Fahrenheit is ideal.
Check the tray daily. Mist if the surface feels dry, but do not overwater. After two to four days, depending on the variety, you will see pale yellow-green shoots pushing up against the cover. When they are about one to two inches tall — usually day three to five — remove the cover and move the tray to light.
Microgreens need moderate light to develop colour and flavour. A sunny south-facing window works for many varieties. If you do not have strong natural light, a basic LED shop light or a dedicated grow light positioned four to six inches above the tray works well. Microgreens are not demanding about light quality — they do not need the intensity required for fruiting plants. Eight to twelve hours of light per day is sufficient.
Once the greens are exposed to light, switch from misting to bottom watering. Pour water into the solid tray underneath and let the growing medium wick it up. This keeps the leaves dry, which dramatically reduces mould risk. Water when the medium feels dry to the touch — typically once or twice per day depending on humidity and airflow.
Harvest Timing and Technique
Harvest timing depends on the variety and your preference, but the general rule is to cut when the first set of true leaves appears. The cotyledon leaves — the first pair that emerges — are present in all seedlings. True leaves are the second set, and they look like miniature versions of the mature plant's leaves.
For most varieties, this happens between seven and fourteen days after sowing. Radish can be as fast as five to seven days. Sunflower and pea shoots typically take ten to fourteen. Do not wait too long — microgreens become tougher and less flavourful as they age, and they will eventually exhaust the nutrients in the seed and growing medium.
To harvest, use sharp scissors or a clean knife and cut the stems just above the soil line. Harvest what you need, or cut the entire tray at once. Microgreens do not regrow after cutting in most cases — unlike baby lettuce, the growing point is removed when you harvest. Plan to compost the spent medium and roots and start a fresh tray.
Unwashed microgreens store best. Place them in a container lined with a dry paper towel, seal loosely, and refrigerate. They will stay fresh for five to seven days. If you need to wash them, spin them gently in a salad spinner and pat dry before storing.
Nutrition Density Compared to Mature Greens
The nutritional profile of microgreens is genuinely impressive. A 2012 study published in the Journal of Agricultural and Food Chemistry analysed twenty-five varieties of microgreens and found that they contained significantly higher concentrations of vitamins C, E, and K, as well as beta-carotene, compared to their mature forms.
Red cabbage microgreens stood out with six times more vitamin C than mature red cabbage. Cilantro microgreens had three times more beta-carotene than mature cilantro. Garnet amaranth microgreens were particularly high in vitamin K. Across the board, microgreens delivered more nutrition per gram than mature vegetables.
This does not mean microgreens replace a varied diet of mature vegetables — you eat them in smaller quantities, after all. But as a nutritional supplement to your meals, they are remarkably efficient. A tablespoon of broccoli microgreens on your sandwich or a handful of sunflower microgreens on your salad adds genuine nutritional value, not just a garnish.
Cost Analysis: Growing vs Buying
The economics of growing microgreens at home are compelling. At the grocery store or farmers market, microgreens typically cost twenty to forty dollars per pound, or three to six dollars for a small two-ounce clamshell container. Growing your own drops the cost by ninety percent or more.
Here is a realistic breakdown for a single ten-by-twenty tray of sunflower microgreens. Seeds cost about fifty cents per tray when bought in bulk. Coconut coir costs roughly twenty cents per tray. Water is negligible. Even factoring in the initial cost of trays — about five dollars for a set of two — your per-tray cost settles to well under a dollar once you are past the initial purchase. Each tray yields four to eight ounces of microgreens, depending on the variety and density of sowing.
Compare that to buying the same quantity at the store: four to eight ounces would cost six to sixteen dollars. Over a year of growing one tray per week, you save roughly three hundred to seven hundred dollars compared to purchasing the same volume. If you eat microgreens regularly, the savings are substantial.
The initial investment is minimal. Two trays, a brick of coir, a spray bottle, and a pound of seeds will cost about fifteen to twenty dollars total. If you need a grow light, a basic LED shop light costs twenty to thirty dollars and will last for years. You can be harvesting your first tray within two weeks of deciding to start.
Troubleshooting Common Problems
Mould is the most common issue new microgreen growers face. White fuzzy growth at the base of stems is usually caused by poor airflow, overwatering, or both. Improve ventilation by placing a small fan nearby on low speed. Switch to bottom watering. Avoid sowing seeds too thickly, as overcrowding traps moisture. If mould appears, you can often save the tray by improving airflow — a light breeze dries the surface and discourages further growth. True mould looks different from root hairs, which are fine white filaments extending from the roots that appear fuzzy but are perfectly normal and harmless.
Uneven germination usually means inconsistent moisture during the blackout phase. Make sure your growing medium is evenly moist before sowing, distribute seeds uniformly, and mist gently after sowing. Pre-soaking larger seeds like sunflower and pea helps ensure they all start at the same time.
Leggy, pale microgreens that stretch and fall over are not getting enough light. Move them closer to a window or lower your grow light. Microgreens that taste bland or bitter may have been grown in too much heat or harvested too late. Keep temperatures moderate and harvest promptly.
For more ideas on what to grow with your microgreen setup, explore our edible gardening guides, which cover everything from countertop herbs to full kitchen gardens.
Frequently Asked Questions
Can I reuse the growing medium after harvesting microgreens?
The spent growing medium and root mat can be composted but should not be reused for another round of microgreens. The roots form a dense mat that is difficult to break up, and reusing the medium increases the risk of mould and disease. Coconut coir and soil are inexpensive enough that starting fresh each time is the practical choice. Toss the root mat into your compost bin or worm bin where it will break down quickly.
Do I need to fertilise microgreens?
No. Microgreens get all the energy they need from the seed itself during their short growing period. The seed contains enough stored nutrients to fuel growth through the cotyledon and first true leaf stages. Adding fertiliser is unnecessary and can actually cause problems — excess nitrogen promotes mould growth and can make microgreens taste bitter. Simply use a good growing medium, provide adequate light and water, and let the seeds do the work.
Are microgreens safe to eat raw?
Yes, microgreens grown at home in clean conditions are safe to eat raw. Unlike sprouts, which are grown in warm, humid, enclosed environments that can harbour bacteria, microgreens grow in open air with good ventilation and are harvested by cutting above the growing medium. Use clean trays, fresh growing medium, and seeds from reputable suppliers. If you have food safety concerns, a gentle rinse before eating is sufficient.
How do I grow microgreens without a sunny window?
A basic LED grow light or even a cool-white LED shop light provides plenty of light for microgreens. Position the light four to six inches above the tray and run it for ten to twelve hours per day using an inexpensive timer. Microgreens are far less demanding about light than fruiting plants like tomatoes, so you do not need an expensive high-output grow light. A twenty-dollar shop light from any hardware store works perfectly well for one or two trays.