Prunus avium – Wild Cherry

Seed germination instructions

Prunus avium (Wild Cherry, Sweet Cherry) produces seeds enclosed in a hard stone and exhibiting physiological dormancy. For reliable and more uniform germination, a two-stage stratification process — warm followed by cold stratification — is recommended.

Mechanical cracking of the stones is not recommended, as it may damage the embryo.

1. Seed soaking

Before stratification, hydrate the seeds:

1. Place the stones in a clean container.

2. Cover them with room-temperature water.

3. Soak for approximately 24 hours.

4. Drain the seeds thoroughly after soaking.

Soaking helps hydrate the seeds and prepares them for the stratification process.

2. Warm stratification

The warm phase is an important part of the dormancy-breaking process.

1. Mix the seeds with slightly moist vermiculite, perlite or clean horticultural sand.

2. Place the seeds and medium in a sealed plastic bag or closed container.

3. Maintain a temperature of approximately 15–20°C (59–68°F).

4. Continue warm stratification for approximately 8–12 weeks.

5. Check the seeds regularly to ensure that the medium remains slightly moist and to monitor for mould.

The medium should be moist but not wet or waterlogged.

3. Cold stratification

After completing the warm stratification stage:

1. Place the sealed bag or container in a refrigerator.

2. Maintain a temperature of approximately 2–5°C (36–41°F).

3. Continue cold stratification for approximately 12–16 weeks.

4. Check the seeds every 1–2 weeks to monitor moisture and their condition.

The seeds must remain moist but should never be submerged in water.

If a seed begins to germinate during stratification, carefully sow it immediately, taking care not to damage the emerging root.

4. Sowing

After completing the stratification process, sow the seeds as soon as possible.

1. Prepare a light, well-drained and well-aerated growing medium.

2. Sow the stones approximately 2–3 cm (0.8–1.2 in) deep.

3. Cover gently with the growing medium.

4. Water moderately.

5. Place the container in a bright location.

Do not attempt to crack or split the stones before sowing, as this can easily damage the embryo.

5. Germination conditions

After sowing, maintain consistent moisture. Do not allow the growing medium to dry out completely, but avoid prolonged waterlogging.

6. Germination time

After successful completion of both stratification stages, the first seedlings may appear approximately 2–6 weeks after sowing.

Germination may be uneven, and some seeds may require additional time.

Do not discard the remaining seeds prematurely if they do not germinate at the same time as the first ones.

7. Care of young seedlings

After emergence:

• provide plenty of light,

• maintain moderate and consistent moisture,

• ensure good air circulation,

• avoid overwatering,

• protect very young seedlings from extreme sunlight and excessive heat.

Once the seedlings have developed several true leaves and a sufficiently developed root system, they can be carefully transplanted into individual pots.

Take care not to damage the young roots during transplanting.

8. Fertilization

Do not fertilize immediately after germination.

Approximately 4–6 weeks after emergence, once the seedlings are well established, begin light fertilization using a balanced fertilizer at approximately 1/4 of the manufacturer's recommended dosage.

9. Common mistakes to avoid

• Skipping the warm stratification stage.

• Using an excessively short stratification period.

• Allowing the seeds to dry out during stratification.

• Keeping the seeds in excessively wet or waterlogged medium.

• Using excessively high temperatures during cold stratification.

• Cracking or splitting the stones and damaging the embryo.

• Sowing the seeds too deeply.

• Excessive watering after sowing.

• Fertilizing young seedlings too early or too heavily.

• Discarding seeds too early because germination is uneven.

Important information

• Prunus avium requires dormancy-breaking treatment for reliable germination.

• A two-stage stratification process — warm followed by cold — is recommended.

• Warm stratification: approximately 8–12 weeks at 15–20°C (59–68°F).

• Cold stratification: approximately 12–16 weeks at 2–5°C (36–41°F).

• Soaking for approximately 24 hours before stratification is recommended.

• Mechanical cracking or scarification of the stone is not required.

• During both stratification stages, the seeds must remain moist but must not be submerged in water.

• Germination may be uneven and some seeds may require additional time.

• Fresh, properly stored seeds generally provide the best results.

Recommended method for beginners

1. Soak the seeds for approximately 24 hours in room-temperature water.

2. Warm-stratify for 8–12 weeks in a slightly moist medium at 15–20°C (59–68°F).

3. Cold-stratify for 12–16 weeks at 2–5°C (36–41°F).

4. After stratification, sow the stones 2–3 cm (0.8–1.2 in) deep in a light, well-drained growing medium.

5. Maintain approximately 15–20°C (59–68°F) after sowing, provide a bright location and keep the growing medium consistently slightly moist.

The first seedlings will usually appear within approximately 2–6 weeks after sowing, although some seeds may germinate later.

Note: Prunus avium has a pronounced seed dormancy, so patience is important.