Quick growing conditions
Air: around 16–24°C; use room-temperature water and avoid overheating the reservoir
Around 5.5–6.0 when using a nutrient solution
Reference feed: 2.0 mS/cm; many crops need a weaker solution or no added fertilizer
14–16 hours daily; approximately 10–18 kilolux under white LEDs
Suitable systems
- tray water culture
Substrates
- hemp mat
- coco coir mat
How to Grow Hydroponic Microgreens at Home
Hydroponic microgreens give you fresh, tender greens to harvest just before eating. They need little space and suit shallow trays under a small grow light.
Microgreens are young edible plants harvested for their stems, seed leaves and emerging true leaves. Many crops are ready within 7–21 days, while slower herbs can take longer.
Growing Conditions
Microgreens include many different crops. Use these guidelines as a starting point and adjust them to the species you grow.
| Parameter | Practical guidance |
|---|---|
| Air temperature | Around 16–24°C suits many common crops. Cooler conditions slow growth; warmth-loving herbs may need higher temperatures. |
| Water or solution temperature | Room-temperature water is usually sufficient for small trays. Avoid overheating a recirculating reservoir. |
| Light duration | Start with 14–16 hours daily once plants are under light. |
| Light intensity | Approximately 10–18 kilolux at leaf level under white LEDs as an initial guide. The useful reading depends on the lamp spectrum and crop. |
| pH | Around 5.5–6.0 when using a nutrient solution. |
| EC | The reference recipe below specifies 2.0 mS/cm. Many crops can use a weaker solution or grow without added fertilizer. |
| Airflow | A gentle breeze across the canopy, without drying the growing mat. |
Temperature, light and nutrient requirements vary between species. Avoid treating one setting as the optimum for every tray.
Choosing Microgreens and a Growing System
Good crops to try include:
- Radish, broccoli and mustard: Fast crops with flavours ranging from mild to peppery.
- Peas: Substantial shoots with a sweet pea flavour.
- Beet and Swiss chard: Colourful stems and leaves.
- Basil and coriander: Aromatic options with slower growth.
Grow crops with different harvest times in separate trays. Use untreated seeds intended for edible microgreen production.
A practical home setup uses a perforated tray inside a solid tray, with a hydroponic growing mat. Hemp, coir and other suitable mats support the roots without garden soil. Keep the mat moist and allow excess water to drain.
Recommended Microgreens Nutrient Solution
This profile comes from Nutrient Solutions for Greenhouse Crops, Geerten van der Lugt and co-authors, version 4, 2020, page 68.
The source identifies it as “Microgreens, water culture.” The values below use the nutrient solution for fertigation column, not the root-zone targets.
All concentrations are mg/L in the finished solution.
| Nutrient | Reference profile, mg/L |
|---|---|
| N, total | 215 |
| N–NO₃ | 203 |
| N–NH₄ | 12 |
| P | 39 |
| K | 211 |
| Ca | 170 |
| Mg | 67 |
| S | 72 |
| Fe | 1.960 |
| Mn | 0.550 |
| Zn | 0.327 |
| B | 0.378 |
| Cu | 0.064 |
| Mo | 0.096 |
Total N already includes N–NO₃ and N–NH₄. P and K are elemental concentrations, not fertilizer oxide values. The source provides one profile without separate stage adjustments.
Use this recipe as a starting point, rather than a requirement for every crop. Short-cycle microgreens can rely heavily on seed reserves, and some can reach harvest without added fertilizer. Feeding can improve growth, particularly on nutrient-free mats or with longer-growing crops.
You can modify the solution during growth according to the crop, source water, lighting and plant response. Include nutrients already present in your water.
Use our NPK Calculator to calculate fertilizer quantities and prepare a weaker version of the reference profile when appropriate.
Watering and Daily Care
Once roots reach the mat, bottom watering helps keep the foliage dry. Add enough water or solution to moisten the mat evenly, without leaving the seedlings submerged.
Check trays daily. Dense growth can trap moisture, so maintain gentle airflow and avoid excessive watering. Microgreens need no pruning or pollination before harvest.
Keep home production free from chemical pesticide treatments. Focus on clean seeds, drinking-quality water, clean trays and regular inspection. Clean equipment between batches.
Harvesting Hydroponic Microgreens
Harvest when the seed leaves are fully expanded and the crop reaches the flavour and size you want, often as the first true leaves emerge.
Use clean, sharp scissors to cut above the growing mat. Keep roots and mat fragments out of the harvested greens. Most microgreen crops provide one harvest; do not expect repeated cutting like mature basil or loose-leaf lettuce.
Harvest dry foliage where possible. Rinse with drinking-quality water before eating, and refrigerate promptly if you are not using the greens immediately.
Common Problems
- Long, weak stems: Check light levels and avoid leaving plants in darkness longer than the crop requires.
- Uneven growth: Check mat moisture, seed distribution and light coverage.
- Collapsing or slimy seedlings: Suspect damping-off or decay. Discard affected trays and clean the equipment.
- Scorched edges or stalled growth: Check solution strength, lamp intensity and whether the mat is drying out.
Have questions about growing hydroponic microgreens? Join the Grow Like Pro Telegram channel. We’re happy to help with your growing questions.
Ranges depend on cultivar, stage, water, and environment.
Calculator overview →Sources
- Nutrient Solutions for Greenhouse Crops, Geerten van der Lugt and co-authors, version 4, 2020, page 68