Green Mizuna Microgreen Seeds

Green Mizuna is a fast-growing brassica microgreen with bright green foliage, mild mustard flavour and distinctive serrated true leaves. It requires no pre-soaking and can generally be harvested in approximately 10–15 days.

What You Need

• Green Mizuna Microgreen Seeds
• A shallow tray with drainage holes
• A solid lower tray for bottom watering
• Coco coir, fine seed-raising mix or another suitable microgreen growing medium
• Clean drinking-quality water
• Fine mist sprayer
• A second tray or suitable blackout cover
• 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:

10–15g dry seed per tray

Spread the seed evenly across the growing surface.

Mizuna performs well at a moderate density. Avoid concentrated piles or excessive overlapping, particularly if you intend to grow the crop until its serrated true leaves begin developing.

For more information about adjusting seed density, see Microgreen Seeding Density.

Pre-Soak

No pre-soaking required.

Sow Green Mizuna seed dry directly onto the prepared growing medium.

Small brassica seeds germinate readily without soaking and are considerably easier to distribute evenly while dry.

Step-by-Step Instructions

1. Clean your equipment. Wash and thoroughly rinse the trays, cover and growing tools.
2. Prepare the growing medium. Add approximately 2–3cm of coco coir, fine seed-raising mix or another suitable medium.
3. Moisten before sowing. Water evenly and allow excess water to drain. The medium should be consistently damp without being saturated.
4. Measure the seed. Use approximately 10–15g for a standard 25 × 50cm tray.
5. Sow evenly. Broadcast the seed over the growing surface and break up any densely seeded patches.
6. Press gently. Ensure good contact between the seed and growing medium.
7. Mist lightly. Use clean drinking-quality water without flooding or moving the seed.
8. Cover the tray. Place another tray or suitable blackout cover over the crop.
9. Check daily. Maintain moisture without keeping the growing medium saturated.
10. Uncover as seedlings establish. Remove the cover once most seedlings are rooted and beginning to push upward.
11. Provide bright light. Move the crop into bright indirect natural light or beneath suitable grow lights.
12. Maintain airflow. Good air movement becomes increasingly important as the serrated foliage develops.
13. Bottom water once rooted. Switch primarily to watering from below once the root system is established.

Blackout

Keep the tray covered for approximately:

2–4 days

Heavy weighting is unnecessary.

A second tray or light cover can help maintain darkness and seed-to-medium contact during early germination.

Use crop development rather than the calendar alone. If seedlings are strongly established before day four, uncover them and move them into light.

For more information about this stage, see Microgreen Blackout Explained.

Germination

Expect germination in approximately:

2–4 days

Mizuna is generally a fast and relatively even germinator under suitable conditions.

Cooler temperatures can slow emergence slightly.

Maintain consistent moisture without flooding or saturating the growing medium.

Temperature

Aim for approximately:

18–24°C

Mizuna is naturally a cool-season brassica and performs well under moderate indoor temperatures.

Avoid excessive heat combined with persistent humidity, particularly in densely grown trays.

Light

Once the covered germination period is complete:

• provide bright indirect natural light or suitable grow lights;
• rotate the tray if needed for even growth;
• maintain good airflow;
• avoid excessive heat; and
• keep the developing foliage from remaining continually wet.

Adequate light encourages compact growth and healthy green foliage.

Watering

During early germination, mist gently whenever necessary to keep the surface evenly moist.

Once roots are established, bottom watering is preferable.

For detailed guidance, see How to Water Microgreens: Misting vs Bottom Watering.

When bottom watering:

• add a shallow amount of water to the lower tray;
• allow the growing medium to absorb moisture;
• check moisture before watering again;
• avoid permanent standing water;
• minimise repeated wetting of established foliage; and
• maintain good airflow.

As Mizuna develops its frilly true leaves, avoiding a constantly wet canopy becomes increasingly important.

Tips for Best Results

• Use approximately 10–15g per 25 × 50cm tray.
• Do not pre-soak.
• Sow evenly at moderate density.
• Keep covered for approximately 2–4 days.
• Expect germination in approximately 2–4 days.
• Maintain approximately 18–24°C.
• Provide bright light after uncovering.
• Maintain good airflow.
• Bottom water once roots establish.
• Avoid permanently saturated growing media.
• Allow the first serrated true leaves to develop for the most characteristic appearance.
• Harvest at approximately 10–15 days.

Allow the True Leaves to Develop

Mizuna initially produces smooth green cotyledons.

As the crop matures, the first true leaves become increasingly cut and serrated, producing the characteristic feathery Mizuna appearance.

The crop can be harvested before this stage, but allowing some true-leaf development generally provides a more distinctive culinary microgreen.

Green & Red Mizuna

Green Mizuna produces fresh green foliage, while Red Mizuna develops red, burgundy and purple tones.

If you want contrasting colour while retaining a similar Mizuna growth habit and flavour profile, see Red Mizuna Microgreen Seeds.

Root Hairs vs Mould

Fine white root hairs can sometimes be mistaken for mould.

Healthy root hairs generally:

• emerge directly from individual roots;
• appear relatively evenly;
• become more noticeable as the root zone dries slightly; and
• become less visible immediately after watering.

Mould is more likely to:

• spread irregularly between seedlings;
• form web-like patches;
• persist after watering; or
• occur alongside slime, decay or unpleasant odours.

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

Discard crops showing obvious spoilage.

Harvest & Storage

Harvest approximately:

10–15 days from sowing

Green Mizuna microgreens are generally ready when:

• the crop is fresh green;
• stems are upright and tender;
• cotyledons are fully open;
• the first serrated true leaves are appearing;
• shoots are approximately 5–8cm tall; and
• the crop has developed its characteristic mild mustard flavour.

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

Where practical, harvest when the foliage is relatively dry.

For more detailed guidance, see How to Harvest & Store Microgreens.

Refrigerate promptly in a clean container. If washed before refrigeration, drain and dry thoroughly first.

Growing as Baby Leaf

Mizuna is also well suited to baby-leaf production.

For baby leaves:

1. Sow substantially less densely than for microgreens.
2. Allow additional space between plants.
3. Continue growing beyond the microgreen stage.
4. Maintain consistent moisture.
5. Provide good light.
6. Harvest when the serrated leaves reach your preferred size.

Growing to Full Maturity

For mature Mizuna:

1. Sow directly or raise seedlings in trays.
2. Transplant or thin to approximately 15–25cm apart.
3. Grow in fertile, well-drained soil.
4. Provide full sun to partial shade.
5. Maintain regular moisture.
6. Harvest larger outside leaves progressively.

Mature Mizuna can be treated as a cut-and-come-again leafy green by leaving the central growing point intact.

Clean Growing / Food Safety

Use clean trays, fresh growing medium, drinking-quality water and clean harvesting equipment.

Maintain:

• controlled moisture;
• good drainage;
• adequate airflow;
• clean harvesting tools; and
• prompt refrigeration after harvest.

Discard crops showing visible mould, slime, decay, abnormal discolouration or an unpleasant smell.

Seed Storage

Store unused Green Mizuna 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 to reduce condensation.