Organic Barley Microgreen Seeds

Organic barley is grown as a dense cereal-grass crop in shallow trays. The grain is pre-soaked, spread evenly over a moist growing medium, established under light pressure, then moved into good light and harvested as young green blades.

If you are familiar with wheatgrass, the overall process is similar. The OzSprout How to Grow Wheatgrass guide also provides useful background on growing dense cereal grasses in trays.

What You Need

• Organic Barley Microgreen Seeds
• A shallow tray with drainage holes
• A solid lower tray for bottom watering
• Coco coir, seed-raising mix or another suitable growing medium
• A clean container for soaking
• Clean drinking-quality water
• A second tray for weighted germination
• An additional weight if light pressure is required
• Bright natural light or suitable grow lights
• Clean scissors or a sharp harvesting knife

Seed Rate

For a standard 25 × 50cm microgreen tray, use approximately:

175–200g dry barley seed per tray

Measure the grain before soaking.

Barley grass is deliberately sown much more densely than small-seeded microgreens, but the grain should still form an even layer rather than deep overlapping piles.

Excessively thick areas can restrict airflow and hold too much moisture around the grain and developing roots.

Pre-Soak

Soak for approximately:

8–12 hours

Use the shorter end of the range in warmer conditions and the longer end in cooler conditions.

1. Measure the dry grain.
2. Rinse thoroughly with clean drinking-quality water.
3. Place it in a clean soaking container.
4. Cover generously with cool water.
5. Soak for approximately 8–12 hours.
6. Drain completely.
7. Rinse once more.
8. Allow excess water to drain before sowing.

Do not leave the grain sitting in standing water after soaking.

Optional Short Pre-Germination

After soaking and draining, the barley can be allowed to rest briefly before sowing until the first tiny root tips begin to appear.

This can help create a more even tray.

If pre-germinating:

1. Keep the drained grain in a clean container.
2. Maintain good drainage.
3. Rinse only when required to prevent drying.
4. Sow once small white root tips begin to emerge.

Do not wait for long roots to develop, as they become harder to spread evenly across the tray.

Step-by-Step Instructions

1. Clean the equipment. Wash and thoroughly rinse the trays, soaking container and tools before starting.
2. Prepare the growing medium. Add approximately 2–3cm of coco coir, seed-raising mix or another suitable medium to the grow tray.
3. Moisten the medium. Water evenly and allow excess water to drain. The medium should be damp throughout without being saturated.
4. Soak the grain. Pre-soak the barley for approximately 8–12 hours and drain thoroughly.
5. Sow evenly. Spread approximately 175–200g dry-seed equivalent evenly across a 25 × 50cm tray.
6. Create good seed contact. Press the grain gently against the growing medium.
7. Stack and apply light pressure. Place a second tray directly over the crop and use light to moderate pressure for approximately 2–3 days.
8. Check daily. Keep the growing medium moist without saturating the grain layer.
9. Remove the weight. Once the roots are established and shoots are developing strongly, remove the added pressure.
10. Continue brief blackout if required. Keep the tray covered for approximately 1–2 additional days if the shoots still need more time to establish before moving into light.
11. Move into light. Once the shoots are well established and pushing upwards, remove the cover and provide bright natural light or suitable grow lights.
12. Maintain airflow. Dense barley grass benefits from consistent airflow around and above the canopy.
13. Bottom water once established. Once the root mat is developed, switch primarily to watering from below.

Weighted Germination

Use approximately:

2–3 days of light to moderate pressure

The purpose of weighting is to maintain close seed-to-medium contact while the roots anchor into the growing medium.

Barley does not need extreme weight.

Remove the pressure once:

• roots are established;
• the grain is firmly anchored; and
• the shoots are pushing strongly upward.

Blackout

After weighted germination, allow approximately:

1–2 additional days of blackout if required

This is separate from weighting.

Not every tray will need the full extra blackout period. Use crop development as the guide.

Move the tray into light once the shoots are established and growing strongly.

Germination

Expect germination in approximately:

2–3 days

Small white roots usually appear first, followed by pale shoots.

Dense cereal-grass trays naturally produce a large root mass, so drainage and airflow are particularly important during this stage.

Temperature

Aim for approximately:

18–24°C

Barley grass performs well under moderate indoor growing temperatures.

Excessive warmth combined with dense sowing and high moisture can quickly create stagnant conditions, so avoid overheating the tray.

Light

Once uncovered:

• provide bright indirect natural light or suitable grow lights;
• maintain consistent light each day;
• avoid prolonged hot direct sunlight; and
• maintain good airflow.

The pale shoots produced during covered growth should turn vivid green after exposure to adequate light.

Watering

Once roots are established, bottom watering is generally preferable.

For more detail, see How to Water Microgreens: Misting vs Bottom Watering.

When watering:

• keep the growing medium consistently moist;
• avoid permanent saturation;
• do not leave the tray standing continuously in deep water;
• reduce unnecessary wetting of the grass blades; and
• maintain airflow throughout the dense canopy.

Barley grass can use substantial water as it develops, but a heavy root mat does not mean it should remain constantly waterlogged.

Tips for Best Results

• Use approximately 175–200g dry grain per 25 × 50cm tray.
• Pre-soak for approximately 8–12 hours.
• Drain thoroughly before sowing.
• Use a dense, even layer rather than deep overlapping piles.
• Pre-germinate briefly if you want more uniform establishment.
• Use 2–3 days of light to moderate weighted germination.
• Treat additional blackout separately from weighting.
• Keep the growing medium moist, not saturated.
• Maintain strong airflow once uncovered.
• Provide good light for vivid green growth.
• Switch to bottom watering after the root mat establishes.
• Harvest while the blades remain young and tender.

Root Hairs vs Mould

Barley develops a dense white root system that can sometimes be mistaken for mould.

Healthy roots generally:

• grow directly from individual grains;
• form an extensive white root mat beneath the crop;
• have a fresh or neutral smell; and
• may appear less fuzzy immediately after watering.

Mould is more likely to:

• spread irregularly across grain surfaces;
• form web-like growth between grains;
• extend onto damaged plant material;
• develop abnormal grey, green or other colouring; or
• occur with slime or a sour or musty smell.

If you are uncertain, see Mould vs Root Hairs on Sprouts & Microgreens.

Discard any crop showing obvious spoilage.

Harvest & Storage

Harvest approximately:

6–10 days from sowing

A typical harvest height is approximately:

10–15cm

Look for:

• vividly green blades;
• upright, healthy growth;
• tender grass;
• an established dense canopy; and
• grass that has not yet become coarse or fibrous.

Cut cleanly just above the growing medium using clean scissors or a sharp harvesting knife.

For juicing, process the freshly harvested grass as soon as practical.

If short-term storage is necessary:

1. Keep the harvested grass relatively dry.
2. Place it loosely in a clean container or produce bag.
3. Refrigerate promptly.
4. Avoid crushing or tightly packing the blades.
5. Discard grass that becomes slimy, heavily wilted or develops an abnormal smell.

Using Fresh Barley Grass

Fresh barley grass is primarily grown for juicing.

It can be:

• juiced on its own;
• combined with wheatgrass;
• used with other fresh ingredients; or
• blended in small quantities where suitable equipment is available.

Because mature cereal-grass blades become increasingly fibrous, harvest young rather than allowing the crop to become overgrown.

Clean Growing / Food Safety

Use clean trays, soaking containers, growing media, water and harvesting equipment.

Pay particular attention to:

• thoroughly rinsing the grain before soaking;
• draining completely after soaking;
• maintaining clean trays;
• avoiding continuously saturated growing media;
• providing good airflow;
• using clean harvesting tools; and
• refrigerating harvested grass promptly when it is not used immediately.

Discard any tray showing visible mould, slime, extensive decay, abnormal discolouration or a sour or unpleasant smell.

Seed Storage

Store unused barley seed sealed in a cool, dry and dark place away from heat, moisture and direct sunlight.

For longer-term storage, refrigeration can help maintain seed viability. Keep refrigerated seed sealed while it returns to room temperature before opening the package to reduce condensation.