Red Veined Sorrel Microgreen Seeds

Red veined sorrel is a slower-growing specialty microgreen that rewards patience with bright green leaves, distinctive crimson veins and a fresh lemony flavour. Unlike fast crops such as radish or broccoli, it is normally allowed to develop its first true leaves before harvest.

If this is your first slower micro-herb crop, the OzSprout How to Grow Microgreens at Home guide explains the general tray-growing process.

What You Need

• Red Veined Sorrel Microgreen Seeds
• A clean tray with drainage, such as the Microgreen & Wheatgrass Grow Tray
• A solid lower tray for bottom watering
• Fine seed-raising mix, propagation mix or a suitable coco-based microgreen medium
• Clean, drinking-quality water
• A fine mist sprayer
• A loose humidity or germination cover if required
• Bright natural light or suitable grow lights

Seed Rate

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

3–5g of seed per tray

Red veined sorrel seed is very small and should be sown relatively lightly.

Because the crop remains in the tray considerably longer than many common microgreens, excessive seeding density can reduce airflow and make moisture management more difficult.

Pre-Soak

No pre-soaking required.

Sow the dry seed directly onto the prepared growing medium.

Step-by-Step Instructions

1. Clean your equipment. Wash and thoroughly rinse the growing tray, lower tray and any tools before sowing.
2. Prepare the growing medium. Add approximately 2–3cm of fine growing medium to the tray. A fine seed-raising or propagation mix works well, as does a suitable Coco Fibre Growing Medium.
3. Moisten before sowing. Wet the medium evenly and allow excess water to drain. It should be consistently moist without being saturated.
4. Sow the seed. Broadcast approximately 3–5g evenly over a 25 × 50cm tray.
5. Press gently. Lightly press the seed against the surface to improve seed-to-medium contact. Do not bury it deeply.
6. Mist carefully. Use a fine spray of clean water to moisten the seed without washing it into clusters.
7. Maintain moisture during germination. A loose humidity or germination cover can be used temporarily if conditions are dry, but heavy weighting and a conventional extended blackout are unnecessary.
8. Allow time to germinate. Germination commonly takes approximately 5–10 days. Be patient; sorrel is noticeably slower than many common microgreens.
9. Move into good light. Once seedlings are emerging and establishing, remove any germination cover and provide bright indirect natural light or suitable grow lights.
10. Maintain airflow. Because the crop remains in the tray for several weeks, good airflow becomes increasingly important as the canopy develops.

Blackout & Weighting

No conventional weighted blackout is required.

Do not apply the type of heavy pressure commonly used for sunflower or pea shoots.

A temporary cover may be used to help maintain humidity during germination, particularly in a dry growing environment, but prolonged darkness is not necessary.

Germination

Expect germination in approximately:

5–10 days

Red veined sorrel is naturally slower and less vigorous during establishment than crops such as radish or broccoli.

Maintain even moisture throughout this stage, but avoid compensating for slow germination by repeatedly saturating the tray.

Temperature

Aim for approximately:

18–24°C

Moderate conditions generally suit the crop well. Avoid excessive heat, particularly once the seedlings are established.

Light

Once seedlings emerge, provide:

• bright indirect natural light or suitable grow lights;
• consistent daily light;
• good airflow; and
• protection from excessive heat.

Good light becomes particularly important as the first true leaves develop and the characteristic crimson-red veining becomes more pronounced.

Watering

Keep the growing medium consistently moist without allowing it to remain waterlogged.

During early germination, mist or gently surface-water when required.

Once the roots are established, switch to bottom watering where practical. This supplies moisture to the root zone while reducing repeated wetting of the foliage.

For a more detailed explanation of the transition, see How to Water Microgreens: Misting vs Bottom Watering.

Do not:

• leave the tray permanently sitting in deep water;
• allow the medium to dry completely during the slow germination period;
• continually soak the foliage; or
• grow the crop in stagnant, humid conditions.

Tips for Best Results

• Do not pre-soak.
• Sow relatively lightly.
• Use a fine growing medium.
• Expect slower germination than most brassica microgreens.
• Do not use heavy weighting.
• Maintain consistent moisture during establishment.
• Avoid waterlogging.
• Switch to bottom watering once roots establish.
• Maintain good airflow throughout the longer growing period.
• Provide good light as the true leaves develop.
• Do not harvest too early if you want the characteristic red veining.

Harvest & Storage

Harvest approximately:

20–30 days from sowing

Rather than relying only on the number of days, look for:

• developed first true leaves;
• clearly visible crimson-red veining;
• healthy upright growth;
• good leaf colour; and
• the desired leaf size and flavour.

Red veined sorrel is usually more visually distinctive once its true leaves have developed, so harvesting it at the same early stage as a fast brassica microgreen can miss much of the crop's appeal.

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

Where practical, harvest when the foliage is relatively dry rather than immediately after watering.

Refrigerate harvested microgreens promptly in a clean container.

Growing as Baby Leaf

For baby leaf production:

1. Sow considerably less densely than for microgreens.
2. Provide additional growing medium and root space.
3. Continue growing beyond the normal microgreen harvest stage.
4. Maintain consistent moisture, light and airflow.
5. Harvest tender young leaves once they reach the preferred size.

Growing as a Mature Herb

Red veined sorrel can also be grown in larger containers or garden beds.

Direct-sow or transplant established seedlings into a suitable position and allow them to develop into mature plants.

Harvest younger outer leaves regularly for the best texture and flavour.

Clean Growing / Food Safety

Use clean trays, equipment, growing media and drinking-quality water.

Good drainage is particularly important because this crop spends considerably longer in the tray than many fast microgreens.

Maintain airflow and avoid continuously saturated growing conditions.

At harvest:

• use clean scissors or a harvesting knife;
• cut above the growing medium;
• keep growing medium and roots out of the harvested crop; and
• refrigerate promptly.

Discard crops showing obvious mould, slime, decay, collapsed growth or an abnormal smell.

Seed Storage

Keep unused seed sealed in a cool, dry and dark location away from heat and moisture.

For longer-term storage, refrigeration can help maintain viability. Allow a sealed refrigerated package to return to room temperature before opening it to reduce the risk of condensation forming on the seed.