Green Shiso Microgreen Seeds

Green Shiso is a slower-growing specialty micro herb with bright green foliage and an aromatic flavour combining mint, basil, anise and subtle spice notes. For the most characteristic crop, allow the first serrated true leaves to begin developing before harvest.

What You Need

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

12–17g dry seed per tray

Spread the seed evenly and avoid excessive density. Green Shiso benefits from sufficient airflow and room for its first true leaves to develop.

Pre-Soak

Pre-soaking is optional.

If soaking, use approximately:

4–8 hours

Drain thoroughly and sow immediately.

Green Shiso can also be sown dry. If sowing without soaking, maintain consistent surface moisture during germination.

Step-by-Step Instructions

1. Clean and thoroughly rinse trays, covers and growing tools.
2. Add approximately 2–3cm of fine seed-raising mix, coco coir or another suitable fine growing medium.
3. Moisten the medium evenly and allow excess water to drain.
4. Spread approximately 12–17g of seed evenly across the surface.
5. Press gently to establish good seed-to-medium contact.
6. Keep the seed shallow. A very fine layer of vermiculite may be used if preferred.
7. Mist gently with clean drinking-quality water.
8. Cover the tray during early establishment.
9. Keep covered for approximately 4–5 days.
10. Remove the cover once germination is well established and seedlings begin pushing upward.
11. Move the crop into bright indirect natural light or beneath suitable grow lights.
12. Maintain good airflow.
13. Bottom water once the root system establishes.
14. Allow the first serrated true leaves to begin developing before harvest.

Covered Germination

Keep the tray covered for approximately:

4–5 days

Green Shiso generally benefits from a longer covered establishment period than fast-growing brassicas.

Do not continue covering the crop once seedlings are well established simply because a few seeds are still emerging.

For more information, see Microgreen Blackout Explained.

Germination

Expect germination in approximately:

3–7 days

Some emergence may continue beyond this period.

Shiso can germinate less uniformly than radish or broccoli, so maintain steady warmth and moisture rather than attempting to force germination with excessive watering.

Temperature

Aim for approximately:

20–25°C

Green Shiso prefers warm growing conditions. Cooler temperatures can significantly slow germination and early development.

Light & True-Leaf Development

Once uncovered, provide bright indirect natural light or suitable grow lights.

The crop begins with rounded cotyledons before developing its characteristic serrated true leaves.

Allowing early true leaves to form generally provides:

• more recognisable Shiso appearance;
• stronger aroma;
• more characteristic flavour; and
• greater culinary value as a specialty micro herb.

Watering

During germination, maintain consistent surface moisture using a fine mist where required.

Avoid flooding or keeping the growing medium permanently saturated.

Once roots establish, bottom watering is preferable.

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

Keep the medium evenly moist while minimising repeated wetting of established foliage.

Harvest & Storage

Harvest approximately:

16–22 days from sowing

Use crop development rather than the calendar alone as the final guide.

Green Shiso microgreens are generally ready when:

• foliage is bright green;
• stems remain tender;
• the first serrated true leaves are opening;
• shoots are approximately 4–8cm tall; and
• the characteristic aromatic Shiso flavour is well developed.

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

For more information, see How to Harvest & Store Microgreens.

Refrigerate promptly in a clean container and avoid crushing the delicate foliage.

Culinary Use

Green Shiso microgreens work particularly well with:

• sushi;
• rice dishes;
• noodles;
• seafood;
• eggs;
• salads;
• Asian-style dishes; and
• plated garnishes.

Because the flavour is concentrated, relatively small amounts are often sufficient.

Root Hairs vs Mould

Fine white root hairs can occasionally be mistaken for mould.

Root hairs generally:

• grow directly from individual roots;
• appear relatively evenly; and
• become less noticeable after watering.

Mould is more likely to:

• spread irregularly between seedlings;
• form web-like growth;
• persist after watering; or
• occur alongside slime, discolouration or unpleasant smells.

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

Discard crops showing obvious spoilage.

Growing Green Shiso to Maturity

Green Shiso can also be grown as a mature annual culinary herb.

For mature plants:

1. Sow shallowly into moist seed-raising mix or prepared soil.
2. Maintain warm, consistent conditions during germination.
3. Keep the seed close to the surface rather than burying deeply.
4. Transplant or thin established plants to approximately 25–30cm apart.
5. Grow in fertile, well-drained soil.
6. Provide full sun to partial shade depending on local climate.
7. Harvest young leaves progressively.

Clean Growing / Food Safety

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

Maintain controlled moisture, good drainage and adequate airflow.

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

Seed Storage

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

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