Paulownia – seed germination instructions

Paulownia seeds are very small and do not require cold stratification or other pre-sowing treatment. They germinate best when exposed to light, with consistent moisture and warm temperatures.

1. Sowing time

The recommended sowing period is February–May when growing indoors, in a greenhouse, or in a heated propagator.

With suitable temperature and lighting, seeds can be sown throughout the year.

2. Growing medium

Use a light, well-drained and preferably sterile seed-starting medium.

Recommended options include:

• commercial seed-starting compost,

• a mixture of peat and perlite at approximately 2:1,

• fine coco coir mixed with perlite.

Moisten the growing medium thoroughly before sowing.

3. Sowing

1. Fill a clean container with the moist growing medium and level the surface.

2. Sprinkle the seeds evenly over the surface.

3. Gently press the seeds onto the surface of the medium.

4. Do not cover the seeds with soil, as light is beneficial for germination.

5. Cover the container with a transparent lid, glass or plastic film to maintain high humidity.

4. Germination conditions

Keep the growing medium evenly moist. Avoid both complete drying and excessive standing water.

Gentle misting or bottom watering is recommended.

5. Germination time

The first seedlings may appear after approximately 5–10 days.

Under suitable conditions, most viable seeds should germinate within approximately 10–21 days.

Older seeds or seeds that have been stored under less favourable conditions may germinate more slowly.

6. Care after germination

Once seedlings appear:

• gradually increase ventilation,

• remove the cover after several days once the seedlings are established,

• provide plenty of light to prevent the seedlings from becoming elongated,

• keep the growing medium moderately moist.

When seedlings have developed 2–4 true leaves, they can be carefully transplanted into individual pots.

7. Fertilization

Young seedlings do not require heavy fertilization.

Approximately 3–4 weeks after germination, light fertilization can be started using a balanced fertilizer for seedlings or green plants at approximately 1/4 of the manufacturer's recommended dosage.

8. Common mistakes to avoid

• Covering the tiny seeds with a thick layer of soil.

• Allowing the growing medium to dry out during germination.

• Using temperatures that are too low.

• Providing insufficient light after emergence.

• Keeping the medium excessively wet, which may lead to fungal growth and damping-off.

Important

Paulownia seeds do not require cold stratification.

For best results, sow the seeds directly on the surface of a moist, well-drained growing medium and provide warmth, light and consistent moisture.

Germination results depend on seed freshness, viability, storage conditions and the environmental conditions provided by the grower.