Red Pak Choi Microgreen Seeds

Red Pak Choi is a fast-growing brassica microgreen with tender green stems, colourful red-purple foliage and a mild, slightly sweet flavour. It requires no pre-soaking and can generally be harvested in approximately 8–14 days.

What You Need

• Red Pak Choi 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.

Aim for consistent coverage without creating thick piles or heavily overlapping patches.

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

Pre-Soak

No pre-soaking required.

Sow Red Pak Choi seed dry directly onto the prepared growing medium.

Small Pak Choi seed germinates readily without soaking and is easier to distribute evenly while dry.

Step-by-Step Instructions

1. Clean your equipment. Wash and thoroughly rinse trays, covers and growing tools.
2. Prepare the growing medium. Add approximately 2–3cm of coco coir, fine seed-raising mix or another suitable fine-textured 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 across the prepared surface and break up any concentrated patches.
6. Press gently. Ensure good contact between the seed and moist growing medium.
7. Mist lightly. Moisten the seed with clean drinking-quality water without flooding the surface.
8. Cover the tray. Place another tray or suitable blackout cover over the crop.
9. Check daily. Maintain even moisture without keeping the growing medium saturated.
10. Uncover once established. Remove the cover when most seedlings have germinated, rooted and begun pushing upward.
11. Provide bright light. Move the tray into bright indirect natural light or beneath suitable grow lights.
12. Maintain good airflow. This helps keep the developing foliage dry and healthy.
13. Bottom water once rooted. Switch primarily to watering from below once the root system establishes.

Blackout

Keep the tray covered for approximately:

2–3 days

Heavy weighting is unnecessary.

Check the crop each day and uncover once the majority of seedlings are rooted and beginning to push upward.

Do not leave an established crop in darkness simply to complete a fixed number of days.

For additional guidance, see Microgreen Blackout Explained.

Germination

Expect germination in approximately:

2–4 days

Pak Choi generally germinates quickly under suitable conditions.

Maintain steady moisture without flooding or waterlogging the growing medium.

Temperature

Aim for approximately:

18–22°C

Moderate temperatures support quick germination and compact growth.

Avoid excessive heat combined with stagnant humidity, particularly during the covered germination period.

Light & Colour Development

Once uncovered:

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

Good light is particularly useful for Red Pak Choi because it encourages:

• compact stems;
• healthy foliage;
• stronger burgundy and purple pigmentation; and
• more uniform growth.

Weak light may result in more elongated seedlings and greener, less distinctive foliage.

Watering

During early germination, mist gently when necessary to maintain surface moisture.

Once roots establish, 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 the medium before adding more water;
• avoid permanent standing water;
• minimise repeated wetting of established foliage; and
• maintain good airflow.

Tips for Best Results

• Use approximately 10–15g per 25 × 50cm tray.
• Use untreated seed suitable for edible microgreen production.
• Do not pre-soak.
• Sow evenly.
• Blackout for approximately 2–3 days.
• Expect germination in approximately 2–4 days.
• Maintain approximately 18–22°C.
• Provide bright light after blackout.
• Maintain good airflow.
• Bottom water once roots establish.
• Avoid permanently saturated growing media.
• Harvest at approximately 8–14 days.

Harvest Stage

Red Pak Choi can be harvested at the cotyledon stage or allowed to grow slightly longer.

Harvesting young provides:

• tender shoots;
• mild flavour; and
• a relatively quick crop.

Allowing the earliest true leaves to begin developing can provide:

• a slightly larger harvest;
• more characteristic Pak Choi foliage; and
• stronger visual colour.

Seed Hulls

Small seed hulls may remain attached to some seedlings during early growth.

Most loosen naturally as the cotyledons expand.

Loose hulls can be gently brushed away where required, but avoid damaging healthy seedlings merely to remove firmly attached hulls.

Root Hairs vs Mould

Fine white root hairs can sometimes be mistaken for mould.

Healthy root hairs generally:

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

Mould is more likely to:

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

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

Discard crops showing obvious spoilage.

Harvest & Storage

Harvest approximately:

8–14 days from sowing

Red Pak Choi microgreens are generally ready when:

• the crop is upright and healthy;
• cotyledons are fully expanded;
• red-purple colour is clearly developing;
• shoots are approximately 5–8cm tall;
• stems remain tender and crisp; and
• the earliest true leaves may be beginning to appear if a larger crop is preferred.

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

For baby-leaf Pak Choi:

1. Sow substantially less densely than for microgreens.
2. Allow more room between plants.
3. Continue growing beyond the microgreen stage.
4. Provide good light.
5. Maintain consistent moisture.
6. Harvest tender leaves at your preferred size.

Growing to Full Maturity

For mature Pak Choi:

1. Direct sow or raise seedlings for transplanting.
2. Sow approximately 5–10mm deep.
3. Thin or transplant established seedlings to approximately 15–25cm apart, depending on the desired mature size.
4. Grow in fertile, well-drained soil.
5. Provide full sun to partial shade.
6. Maintain consistent moisture.

Pak Choi generally performs best in mild to cool conditions. Temperature stress can encourage premature bolting.

Clean Growing / Food Safety

Use untreated seed suitable for edible microgreen production.

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

Maintain:

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

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

Seed Storage

Store unused Red Pak Choi 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.