Microgreens grow from seed to harvest in 7 to 21 days on a kitchen counter, packing 4 to 40 times the nutrient density of mature greens (USDA, 2012). A 10×20 inch tray yields 8 to 16 ounces of cut greens for under $3 in seed and soil — the same volume costs $7 to $12 at a grocery store. This guide covers every decision: trays, soil, seeds, lighting, watering, harvesting, and the equipment matrix that separates a $40 starter kit from a $400 production setup. Microgreens are project #5 in our simple family gardening projects roundup for families.
What Are Microgreens?
Microgreens are vegetable, herb, and grain seedlings harvested at the first true leaf stage — typically 1 to 3 inches tall, 7 to 21 days after sowing. Unlike sprouts (eaten whole, root included, grown in water), microgreens grow in a soil or fiber medium and are cut just above the soil line at harvest.
The category was popularized by California chefs in the 1980s, but home growers now drive the market. Forty common species qualify as microgreens, ranging from fast crops like radish (8 days) to slower ones like cilantro (21 days). Nutrient research published in the Journal of Agricultural and Food Chemistry (2012) found microgreens averaged 5x the vitamin C and 4x the carotenoids of their mature counterparts.
Microgreens vs Sprouts vs Baby Greens
The three categories are commonly confused but differ in growing method, harvest stage, and food safety profile. Sprouts grow in standing water with no soil — a high-moisture environment that has caused 55+ documented foodborne illness outbreaks since 1996 (FDA). Microgreens grow in a drained soil medium and are cut, not pulled, eliminating most of that risk. Baby greens are the same plants harvested 30 to 50 days later at 4+ inch height.
| Attribute | Sprouts | Microgreens | Baby Greens |
|---|---|---|---|
| Growing medium | Water only | Soil or fiber mat | Soil |
| Days to harvest | 3 to 7 | 7 to 21 | 30 to 50 |
| Harvest method | Pull whole plant | Cut above soil | Cut above soil |
| Edible parts | Root, stem, seed leaves | Stem, cotyledons, first true leaves | Stem, full leaves |
| Light required | None or minimal | 4 to 6 days under light | Full grow cycle |
| Yield per 10×20 tray | 1 to 2 lbs (wet) | 8 to 16 oz | 4 to 8 oz |
| Foodborne illness risk | High (warm, wet) | Low | Low |
| Nutrient density | High (live enzymes) | Highest (4-40x mature) | Moderate |
For a deeper dive on the sprouting side, see our Sprouting Seeds at Home guide, which covers jar-based and bag-based methods for sprouts specifically.
Equipment You Actually Need
A working microgreens setup has six pieces: trays, growing medium, seeds, light source, water spray bottle, and a humidity dome. Every other accessory is optional. Total cost for a single-tray setup: $35 to $60. A 4-tray rack with grow light: $120 to $200.
Trays
The standard is the 10-inch by 20-inch (1020) flat. Buy two per tray slot — one with drain holes (the grow tray), one solid (the watering reservoir or “bottom-watering” tray). Plastic trays cost $1 to $3 each; heavy-duty injection-molded trays from suppliers like Bootstrap Farmer last 5+ years and cost $4 to $8 each. The cheap ones crack within 6 to 12 cycles.
Growing Medium
Three options dominate: peat-based seed starting mix, coco coir, or hemp grow mats. Peat mix is cheapest ($0.30 per tray) and most familiar, but compacts over reuses. Coco coir ($0.50 per tray) drains better and is renewable. Hemp mats ($1 per tray) are the cleanest option for indoor kitchens but cost more per cycle. If you go that route, the hydroponic microgreens setup guide covers the wicking-tray system that turns hemp mats into a low-maintenance kitchen production setup.
Seeds
Use seeds labeled as microgreen seeds or untreated bulk seeds — never seed packets sold for outdoor garden planting (often coated with fungicide). One ounce of radish seed sows roughly 4 to 6 trays. Bulk pricing through True Leaf Market or Johnny’s Selected Seeds runs $10 to $25 per pound for common varieties.
Lighting
Microgreens need light only after germination (days 4 to 6 onward). A T5 fluorescent fixture or any LED grow light delivering 200 micromoles per square meter per second (PPFD) at the canopy works. Hanging height: 8 to 12 inches above the trays. Run lights 12 to 16 hours per day. Skip the high-end horticultural lights — microgreens are short cycle and don’t need PPFD above 300.
If you’re new to indoor growing in general, the Indoor Growing complete guide covers light selection, humidity, and ventilation for any indoor crop.
Water Spray Bottle
A 32-ounce trigger sprayer is the workhorse for the first 5 days (germination phase). After that, switch to bottom-watering by pouring water into the solid tray underneath. This stops mold and damping-off, the two failure modes that kill 90% of beginner trays.
Humidity Dome
A clear plastic dome covers the tray for the first 4 days to keep humidity at 80 to 95 percent during germination. Many trays come with matching domes; otherwise, an inverted second tray works.
Best Microgreens for Beginners
Start with one or two of these high-success species before branching out. They germinate fast, resist disease, and tolerate inconsistent watering — three forgiving traits for first-time growers.
- Radish (any variety): 8 days to harvest, peppery flavor, almost foolproof. The single best beginner crop.
- Sunflower (black oil): 10 to 14 days, nutty crunchy flavor, highest yield per tray (12 to 18 oz). Requires hull removal.
- Pea shoots: 10 to 14 days, sweet, robust seedlings. Pre-soak seeds 8 to 12 hours.
- Broccoli: 10 days, mild flavor, sulforaphane content (cancer research interest).
- Mustard: 8 to 10 days, sharp wasabi-like heat, fast germination.
Avoid these on your first 5 trays: cilantro (slow, 18 to 21 days), basil (slow and finicky), beets (15+ days, low germination), and any allium (onion, leek — slow and easily moldy).
Step-by-Step Growing Process
The cycle has four phases: sow, germinate (covered), light (uncovered), and harvest. The whole process takes 8 to 14 days for fast crops, 18 to 21 for slower ones.
Day 0: Sow
Fill the drain-hole tray with 1.5 inches of pre-moistened medium. Press flat with a second tray. Scatter seeds at the rate of 1 to 1.5 ounces per 1020 tray for small seeds (radish, mustard, broccoli) or 2 to 3 ounces for large seeds (sunflower, pea). Press seeds into the surface — do not bury them. Mist with water until the surface is uniformly damp. Cover with a humidity dome or weight.
Days 1 to 4: Germinate
Keep covered in the dark at 65 to 75°F. Mist twice daily if the medium dries on top. A weight on top of the dome (8 to 10 lbs for small seeds) forces roots downward and produces denser, taller stems — a technique called “blackout pressing.”
Days 4 to 6: Uncover and Light
Once seedlings reach 1 inch tall and the cotyledons (seed leaves) start opening, remove the dome and place under light. Switch to bottom-watering. Lights run 12 to 16 hours per day.
Days 7 to 21: Grow to Harvest
Bottom-water once daily — pour 1/2 to 1 cup of water into the solid tray below. Watch for the first true leaf appearing between the cotyledons. That is the harvest signal.
Lighting Setup Specifics
The most common beginner mistake is leftover-incandescent or warm-white kitchen lighting. Microgreens need photosynthetically active radiation (PAR), not just visible light. A 4-foot T5 fluorescent fixture with two bulbs ($30 to $50) works fine for a single 1020 tray. For a 4-tray vertical rack, an LED grow bar with 100 to 150 watts of actual draw covers the area at 8-inch hang height.
Hours per day matter more than wattage. Twelve hours at 200 PPFD produces taller, leggier plants; 16 hours at 200 PPFD produces denser, stockier plants. For most crops, set a timer for 14 hours and ignore it.
Watering Schedule by Phase
| Day | Method | Frequency | Why |
|---|---|---|---|
| 0 (sow) | Top mist | Once, until damp | Wet seeds for germination |
| 1 to 3 | Top mist | 1 to 2x daily | Maintain humidity under dome |
| 4 | Top mist or bottom | 1x daily | Transition phase |
| 5 to 7 | Bottom water | Daily, 1/2 cup | Cotyledons open, roots reach bottom |
| 8 to harvest | Bottom water | Daily or every other day, 1 cup | Mature canopy, higher transpiration |
Bottom-watering is the single most important technique to learn. Wet leaves at any stage past Day 4 invite mold (typically Pythium or Rhizoctonia). The water should sit in the bottom tray for 15 to 30 minutes — if any water remains after 30 minutes, you over-watered. Pour it out.
Harvesting and Storage
Cut microgreens with sharp scissors or a chef’s knife held parallel to the soil surface, taking the stem and cotyledons but leaving the roots in the medium. Most crops harvest at 1.5 to 3 inches tall — sunflower and pea shoots can grow to 4 inches before they start to yellow.
For the longest shelf life, harvest dry — do not water for 8 to 12 hours before cutting. Spin-dry briefly if leaves are damp. Store in a sealed container with a paper towel at the bottom (absorbs condensation) at 36 to 40°F. Properly dried radish or broccoli microgreens keep 7 to 10 days. Sunflower and pea shoots keep 5 to 7 days. Wet harvest cuts that to 3 days.
Common Problems and Solutions
White fuzz on the soil: 90% of the time this is root hairs (normal, fine, fuzzy in patches around stems), not mold. Mold appears as web-like spots on leaves or stems and smells musty. If real mold appears, increase airflow, reduce watering, and replace the soil for next cycle.
Yellow seedlings: Either insufficient light (move closer or extend hours) or root rot from over-watering (too-wet medium, no drainage in bottom tray). Cut the cycle losses, sterilize the tray, restart.
Uneven germination: Old seeds (test germination by paper-toweling 10 seeds; if fewer than 7 sprout in 5 days, replace stock) or uneven soil moisture during sowing.
Damping-off (seedlings flop over and die at the soil line): Pythium fungus. Cut watering, increase airflow, and never reuse soil from a damping-off tray. Sanitize trays with diluted hydrogen peroxide (1:8 in water) between cycles.
For a broader pest and contamination guide, see our Fungus Gnats in Houseplants guide — fungus gnat larvae are the second most common indoor microgreen pest after mold.
Cost: Growing vs Buying
| Source | Quantity | Cost | Per Ounce |
|---|---|---|---|
| Whole Foods (clamshell) | 1.5 oz | $5.99 | $3.99 |
| Farmers market | 2 oz | $6.00 | $3.00 |
| DIY radish (1020 tray) | 10 oz | $2.50 | $0.25 |
| DIY sunflower (1020 tray) | 14 oz | $3.20 | $0.23 |
| DIY broccoli (1020 tray) | 9 oz | $3.80 | $0.42 |
The startup cost (rack, lights, trays, dome) is $80 to $200, recouped in 6 to 12 weeks of weekly trays for a household that eats 3 to 5 ounces per week. Beyond that, the marginal cost is just seeds and soil.
Where to Set Up
Microgreens tolerate 60 to 80°F and don’t need direct sunlight (they need grow lights). A kitchen counter, basement shelving, garage in mild climates, or a closet with a fan all work. They need good airflow — a small clip-on fan running 2 to 3 hours per day cuts mold risk by an estimated 80 to 90 percent.
For apartment renters with limited space, see our Grow Lettuce Inside guide — the same tabletop setup works for microgreens at a smaller footprint.
Scaling Up
Once two trays per week becomes routine, the next step is a 4-tier rack with timed lights and a watering schedule. A typical home production setup at this scale yields 2 to 3 lbs of microgreens per week — enough to supply a household plus sell or trade extras. Successful at-home growers in the 16+ tray range often shift to commercial trays, blackout shelves, and bulk seed buying through co-ops or directly from farms.
Selling microgreens to local restaurants, farmers markets, and CSA shareholders is a viable side business at $20 to $40 per pound wholesale. The legal angle (cottage food laws, food handler permits, sales tax) varies by state — check your state’s department of agriculture website before selling.
How long do microgreens take to grow?
Most microgreens harvest in 7 to 14 days. Radish is the fastest at 8 days. Sunflower and pea shoots take 10 to 14. Cilantro and basil are slowest at 18 to 21 days. Speed depends on temperature, light hours, and seed freshness.
Can you regrow microgreens after cutting?
No. Microgreens are harvested at the first true leaf stage and lack the leaf surface to regrow. Pea shoots are the one exception — they may produce a smaller second flush 7 to 10 days after the first cut, but yield drops 50 to 70 percent.
Do microgreens need sunlight?
They need light, not necessarily sunlight. A south-facing window provides enough for slow growth, but most home growers use T5 fluorescent or LED grow lights running 12 to 16 hours daily for consistent yields and color. Microgreens require light only after Day 4.
What are the easiest microgreens to grow?
Radish is the easiest — 8 days to harvest, near 100 percent germination, tolerates over- and under-watering. Sunflower, pea shoots, broccoli, and mustard are the next four most beginner-friendly. Avoid cilantro, basil, and onion family until comfortable with the basics.
Are microgreens really more nutritious than mature greens?
Research from the USDA (2012) found microgreens contain 4 to 40 times the nutrient density of their mature counterparts, with red cabbage, cilantro, and amaranth showing the highest concentrations of vitamins C, E, and K and beta-carotene.
What is the difference between microgreens and sprouts?
Sprouts grow in water with no soil and are eaten whole including roots, harvested at 3 to 7 days. Microgreens grow in soil or fiber, are cut above the soil line at 7 to 21 days, and only the stem and leaves are eaten. Microgreens have a much lower foodborne-illness risk.
Can you grow microgreens without soil?
Yes. Hemp mats, jute mats, coco coir, and hydroponic pads all work as soil-free media. They cost more per cycle ($1 to $2 per tray vs $0.30 to $0.50 for soil) but produce cleaner harvests and are easier to dispose of.
Microgreens Deep-Dive Cluster
For specific topics in depth, the four pillar articles in this cluster cover the questions home growers ask after their first tray:
- Microgreens vs Sprouts: 8 Critical Differences — nutrient density, food safety, cost, and yield compared head-to-head.
- Microgreens Trays: 1020s, Drainage, and Stacking — why heavy-duty trays last 5+ years and cheap nursery flats don’t.
- 12 Best Microgreens to Grow at Home — ranked by speed, yield, difficulty, and flavor with the recommended first-three-trays starter set.
- Microgreens Harvest: Cut, Wash, Store — the 8-12 hour pre-harvest dry, cut height per species, and the 36-40°F storage that gets you 7-10 days of shelf life.