What is stratification?
Stratification is the process of treating seeds to simulate the natural growing conditions they need to germinate. The seeds of many tree species are genetically programmed to survive winter and germinate in early spring. This helps them maximize the length of their first growing season. Most of these seeds can only grow after a period of cold weather.
So when planting seeds for bonsai from different climates, or when planting out of season, it may be necessary to simulate a cold season to increase the germination rate. Most tree species will require soaking their seeds in water before storing them in your refrigerator for a month or two. The exact duration and optimal temperature depend on the species of tree, here is a summary table for the seeds present in the Bonsai Box :
| Tree species | Number of days required for stratification | Temperature for stratification |
| Colorado Blue Spruce | No stratification period necessary | No stratification period necessary |
| Chinese Fir | 30 to 60 days | 4 °C (39 °F) |
| Japanese Cedar | 90 to 120 days | 4 °C (39 °F) |
| Eastern Juniper | 90 to 120 days | 4 °C (39 °F) |
Here are the stratification tips for the species in the Bonsai Box Deluxe :
|
Tree species |
Hydration |
Number of days required for stratification |
Temperature for stratification |
|
Rocky Pine |
24 hours |
No stratification period necessary |
No stratification period necessary |
|
Colorado Blue Spruce |
24 hours |
No stratification period necessary |
No stratification period necessary |
|
Tamarack larch |
12 hours |
2 weeks |
4°C (39°F) |
|
Lodgepole Pine |
24 hours |
1 month |
4°C (39°F) |
|
Chinese Fir |
24 hours |
1 month |
4°C (39°F) |
|
Eastern Juniper |
24 hours |
3 months |
4°C (39°F) |
|
Japanese Cedar |
24 hours |
3 months |
4°C (39°F) |
|
Red Mapple |
24 hours |
4 months |
4°C (39°F) |
How to do seed stratification?
- After soaking the seeds for 24 hours in water at room temperature,
- Take two sheets of paper towel,
- Spray the paper towel sheets with plenty of water without the paper towel sheet decomposing.
- Place the seeds on one side and fold the paper towel over so that they are well protected.
- Store securely in a Ziploc with a label to indicate the tree species.
- Store the ziploc in the fridge.
- Put a reminder in the calendar of the number of days needed.
Do not hesitate to contact us with any questions and order your Bonsai Box now to introduce yourself to the art of Bonsais!
